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Sample records for perform nuclear resonance

  1. Nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    1983-06-01

    This report summarises the aspects of nuclear magnetic resonance imaging (NMRI) considered by the National Health Technology Advisory Panel and makes recommendations on its introduction in Australia with particular regard to the need for thorough evaluation of its cost effectiveness. Topics covered are: principles of the technique, equipment required, installation, costs, reliability, performance parameters, clinical indications, training and staff requirements, and safety considerations

  2. Resonant cell of a double nuclear electron resonance spectrometer for performance in a 120-350 Gs magnetic field

    International Nuclear Information System (INIS)

    Baldin, V.I.; Stepanov, A.P.

    1976-01-01

    Spectrometer double-frequency resonance cell construction of a double nuclear electron resonance for operation in 120-350 Gs magnetic fields is described. The cell has been developed from a special decimeter resonator with a concentrated capacitance. The electric and magnetic components of a high frequency field are efficiently divided in the separator. Therefore, the insertion of a measuring coil and a sample in the maximum of the magnetic component of the field does not practically affect the distribution and parameters of the high-frequency field. The double-frequency resonance cell proposed provides for a higher accuracy of measuring amplifications of the nuclear magnetic resonance signals when there is the overhauzer effect for 120-350 Gs magnetic fields

  3. Nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Ethier, R.; Melanson, D.; Peters, T.M.

    1983-01-01

    Ten years following computerized tomography, a new technique called nuclear magnetic resonance revolutionizes the field of diagnostic imaging. A major advantage of nuclear magnetic resonance is that the danger of radiation is non-existent as compared to computerized tomography. When parts of the human body are subject to radio-frequencies while in a fixed magnetic field, its most detailed structures are revealed. The quality of images, the applications, as well as the indications are forever increasing. Images obtained at the level of the brain and spinal cord through nuclear magnetic resonance supercede those obtained through computerized tomography. Hence, it is most likely that myelography, along with pneumoencephalography will be eliminated as a diagnostic means. It is without a doubt that nuclear magnetic resonance is tomorrow's computerized tomography [fr

  4. Nuclear magnetic resonance gyroscope

    International Nuclear Information System (INIS)

    Grover, B.C.

    1984-01-01

    A nuclear magnetic resonance gyro using two nuclear magnetic resonance gases, preferably xenon 129 and xenon 131, together with two alkaline metal vapors, preferably rubidium, potassium or cesium, one of the two alkaline metal vapors being pumped by light which has the wavelength of that alkaline metal vapor, and the other alkaline vapor being illuminated by light which has the wavelength of that other alkaline vapor

  5. Nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Young, I.R.

    1984-01-01

    In a method of imaging a body in which nuclear magnetic resonance is excited in a region including part of the body, and the free induction decay signal is measured, a known quantity of a material of known nuclear magnetic resonance properties, for example a bag of water, is included in the region so as to enhance the measured free induction decay signal. This then reduces the generation of noise during subsequent processing of the signal. (author)

  6. Nuclear Magnetic Resonance Spectroscopy

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 9; Issue 1. Nuclear Magnetic Resonance Spectroscopy. Susanta Das. General Article Volume 9 Issue 1 January 2004 pp 34-49. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/009/01/0034-0049. Keywords.

  7. Nuclear magnetic resonance apparatus

    International Nuclear Information System (INIS)

    Lambert, R.

    1991-01-01

    In order to include the effect of a magnetic object in a subject under investigation, Nuclear Magnetic Resonance (NMR) apparatus is operable at more than one radio frequency (RF) frequency. The apparatus allows normal practice as far as obtaining an NMR response or image from a given nuclear species is concerned, but, in addition, interrogates the nuclear spin system at a frequency which is different from the resonance frequency normally used for the given nuclear species, as determined from the applied magnetic field. The magnetic field close to a magnetised or magnetisable object is modified and the given nuclear species gives a response at the different frequency. Thus detection of a signal at the frequency indicates the presence of the chosen nuclei close to the magnetised or magnetisable object. Applications include validation of an object detection or automatic shape inspection system in the presence of magnetic impurities, and the detection of magnetic particles which affect measurement of liquid flow in a pipe. (author)

  8. Nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Rueterjans, H.

    1987-01-01

    Contributions by various authors who are working in the field of NMR imaging present the current status and the perspectives of in-vivo nuclear magnetic resonance spectroscopy, explaining not only the scientific and medical aspects, but also technical and physical principles as well as questions concerning practical organisation and training, and points of main interest for further research activities. (orig./TRV) [de

  9. Performance assessment of self-interrogation neutron resonance densitometry for spent nuclear fuel assay

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Jianwei, E-mail: huj1@ornl.gov [Reactor and Nuclear Systems Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, PO Box 2008, MS-6172, Oak Ridge, TN 37831-6172 (United States); Tobin, Stephen J.; LaFleur, Adrienne M.; Menlove, Howard O.; Swinhoe, Martyn T. [Nuclear Engineering and Nonproliferation Division, Los Alamos National Laboratory (United States)

    2013-11-21

    Self-Interrogation Neutron Resonance Densitometry (SINRD) is one of several nondestructive assay (NDA) techniques being integrated into systems to measure spent fuel as part of the Next Generation Safeguards Initiative (NGSI) Spent Fuel Project. The NGSI Spent Fuel Project is sponsored by the US Department of Energy's National Nuclear Security Administration to measure plutonium in, and detect diversion of fuel pins from, spent nuclear fuel assemblies. SINRD shows promising capability in determining the {sup 239}Pu and {sup 235}U content in spent fuel. SINRD is a relatively low-cost and lightweight instrument, and it is easy to implement in the field. The technique makes use of the passive neutron source existing in a spent fuel assembly, and it uses ratios between the count rates collected in fission chambers that are covered with different absorbing materials. These ratios are correlated to key attributes of the spent fuel assembly, such as the total mass of {sup 239}Pu and {sup 235}U. Using count rate ratios instead of absolute count rates makes SINRD less vulnerable to systematic uncertainties. Building upon the previous research, this work focuses on the underlying physics of the SINRD technique: quantifying the individual impacts on the count rate ratios of a few important nuclides using the perturbation method; examining new correlations between count rate ratio and mass quantities based on the results of the perturbation study; quantifying the impacts on the energy windows of the filtering materials that cover the fission chambers by tallying the neutron spectra before and after the neutrons go through the filters; and identifying the most important nuclides that cause cooling-time variations in the count rate ratios. The results of these studies show that {sup 235}U content has a major impact on the SINRD signal in addition to the {sup 239}Pu content. Plutonium-241 and {sup 241}Am are the two main nuclides responsible for the variation in the count

  10. Giant nuclear resonances

    International Nuclear Information System (INIS)

    Snover, K.A.

    1989-01-01

    Giant nuclear resonances are elementary mods of oscillation of the whole nucleus, closely related to the normal modes of oscillation of coupled mechanical systems. They occur systematically in most if not all nuclei, with oscillation energies typically in the range 10-30 MeV. One of the best - known examples is the giant electric dipole (El) resonance, in which all the protons and all the neutrons oscillate with opposite phase, producing a large time - varying electric dipole moment which acts as an effective antenna for radiating gamma ray. This paper discusses this mode as well as quadrupole and monopole modes

  11. Advanced Nuclear Magnetic Resonance

    OpenAIRE

    Alonso, Diego A.

    2014-01-01

    Transparencias en inglés de la asignatura "Resonancia Magnética Nuclear Avanzada" (Advanced Nuclear Magnetic Resonance) (36643) que se imparte en el Máster de Química Médica como asignatura optativa de 3 créditos ECTS. En esta asignatura se completa el estudio iniciado en la asignatura de quinto curso de la licenciatura en Química "Determinación estructural" (7448) y en la del Grado de Química de tercer curso "Determinación estructural de los compuestos orgánicos" (26030) en lo referente a té...

  12. Nuclear magnetic resonance scattering

    International Nuclear Information System (INIS)

    Young, I.R.

    1985-01-01

    A nuclear magnetic resonance apparatus is described including a magnet system which is capable of providing a steady magnetic field along an axis, and is constructed so as to define a plurality of regions along the axis in each of which the field is substantially homogeneous so that in each region an imaging operation may be separately carried out. Iron shields increase the field homogeneity. In use, each patient lies on a wheeled trolley which is provided with magnetic field gradient coils and an RF coil system, some of the coils being movable to facilitate positioning of the patient, and there are terminals for connection to a common computing and control facility. (author)

  13. Nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Cremin, B.J.

    1981-01-01

    Recent advances in diagnostic imaging, have been the medical application of nuclear magnetic resonance (NMR). It's been used to study the structure of various compounds in chemistry and physics, and in the mid-1970 to produce images of rabbits and eventually of the human hand and head. The images are produced by making use of the nuclear magnetization of the hydrogen ion, or proton, that is present in biological material to record the density distribution of protons in cellular water and lipids. An exploration of the end-results of complicated free induction decay signals, that have been digitized and frequency-analysed by mathematical computerized techniques to produce an image of tissue density, is given. At present NMR produces images comparable to those of early computed tomography

  14. Nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Rabenstein, D.L.; Guo, W.

    1988-01-01

    Nuclear magnetic resonance (NMR) spectroscopy is one of the most widely used instrumental methods, with applications ranging from the characterization of pure compounds by high-resolution NMR to the diagnosis of disease by magnetic resonance imaging (MRI). To give some idea of the wide-spread use of NMR, a computer search for the period 1985-1987 turned up over 500 books and review articles and over 7000 literature citations, not including papers in which NMR was used together with other spectroscopic methods for the routine identification of organic compounds. Consequently, they have by necessity been somewhat selective in the topics they have chosen to cover and in the articles they have cited. In this review, which covers the published literature for the approximate period Sept 1985-Aug 1987, they have focused on new developments and applications of interest to the chemist. First they review recent developments in instrumentation and techniques. Although there have not been any major break-throughs in NMR instrumentation during the past two years, significant refinements have been reported which optimize instrumentation for the demanding multiple pulse experiments in routine use today. Next they review new developments in methods for processing NMR data, followed by reviews of one-dimensional and two-dimensional NMR experiments

  15. The nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Goyer, Ph.

    1997-01-01

    The spectroscopy of nuclear magnetic resonance constitutes a major analytical technique in biological and organic analysis. This technique appears now in the programme of preparatory classes and its teaching is developed in the second year of DEUG. The following article reviews on the nuclear magnetic resonance and on the possibilities it offers to bring to the fore the physico-chemical properties of molecules. (N.C.)

  16. Fourier transform nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Geick, R.

    1981-01-01

    This review starts with the basic principles of resonance phenomena in physical systems. Especially, the connection is shown between the properties of these systems and Fourier transforms. Next, we discuss the principles of nuclear magnetic resonance. Starting from the general properties of physical systems showing resonance phenomena and from the special properties of nuclear spin systems, the main part of this paper reviews pulse and Fourier methods in nuclear magnetic resonance. Among pulse methods, an introduction will be given to spin echoes, and, apart from the principle of Fourier transform nuclear magnetic resonance, an introduction to the technical problems of this method, e.g. resolution in the frequency domain, aliasing, phase and intensity errors, stationary state of the spin systems for repetitive measurements, proton decoupling, and application of Fourier methods to systems in a nonequilibrium state. The last section is devoted to special applications of Fourier methods and recent developments, e.g. measurement of relaxation times, solvent peak suppression, 'rapid scan'-method, methods for suppressing the effects of dipolar coupling in solids, two-dimensional Fourier transform nuclear magnetic resonance, and spin mapping or zeugmatography. (author)

  17. Nuclear magnetic resonance diagnostic apparatus

    International Nuclear Information System (INIS)

    Sugimoto, H.

    1985-01-01

    Nuclear magnetic resonance diagnostic apparatus including a coil for generating a gradient field in a plane perpendicular to a static magnetic field, means for controlling the operation of the coil to rotationally shift in angular steps the gradient direction of the gradient field at an angle pitch of some multiple of the unit index angle through a plurality of rotations to assume all the shift positions of the gradient direction, a rough image reconstructor for reconstructing a rough tomographic image on the basis of nuclear magnetic resonance signals acquired during a rotation of the second gradient magnetic field, a rough image display for depicting the rough tomographic image, a final image reconstructor for reconstructing a final tomographic image on the basis of all nuclear magnetic resonance signals corresponding to all of the expected rotation shift positions acquired during a plurality of rotations and a final image display for depicting the final tomographic image

  18. Fingerprinting analysis of Saposhnikovia divaricata using 1H nuclear magnetic resonance spectroscopy and high performance liquid chromatography.

    Science.gov (United States)

    Xin, Yue-Yang; Deng, An-Jun; Du, Guan-Hua; Zhang, Jin-Lan; Qin, Hai-Lin

    2010-09-01

    The (1)H nuclear magnetic resonance ((1)H NMR) fingerprints of fractionated non-polar and polar extracts (control substance for plant drug [CSPD] A and B) from the roots of 12 specimens of Saposhnikovia divaricata (Turcz.) Schischk were achieved with Fourier Transform (FT)-NMR spectrometer and assigned by comparison to each other and to the (1)H NMR spectra of the isolated individual compounds. These fingerprints were found to be uniform in terms of the specificity for the implication of all 12 specimens being systematically of the same origin. The uniformity was further affirmed by high performance liquid chromatography (HPLC), which also revealed exactly identical specificity for the identified S. divaricata species with the (1)H NMR appearances of corresponding CSPD on the part of the composition of characteristic constituents when comparing to corresponding individual compounds. This investigation unambiguously shows that the specific signals from the chemotaxonomically significant compounds of chromones and coumarins in S. divaricata are exhibited distinctively in the composite features of both (1)H NMR fingerprints and HPLC profiles. The (1)H NMR and HPLC profiles established can successfully be used as reference for the authentication of the origin of S. divaricata species as well as for chemotaxonomic studies.

  19. Evanescent Waves Nuclear Magnetic Resonance

    DEFF Research Database (Denmark)

    Halidi, El Mohamed; Nativel, Eric; Akel, Mohamad

    2016-01-01

    Nuclear Magnetic Resonance spectroscopy and imaging can be classified as inductive techniques working in the near- to far-field regimes. We investigate an alternative capacitive detection with the use of micrometer sized probes positioned at sub wavelength distances of the sample in order...

  20. Determination of avermectins by the internal standard recovery correction - high performance liquid chromatography - quantitative Nuclear Magnetic Resonance method.

    Science.gov (United States)

    Zhang, Wei; Huang, Ting; Li, Hongmei; Dai, Xinhua; Quan, Can; He, Yajuan

    2017-09-01

    Quantitative Nuclear Magnetic Resonance (qNMR) is widely used to determine the purity of organic compounds. For the compounds with lower purity especially molecular weight more than 500, qNMR is at risk of error for the purity, because the impurity peaks are likely to be incompletely separated from the peak of major component. In this study, an offline ISRC-HPLC-qNMR (internal standard recovery correction - high performance liquid chromatography - qNMR) was developed to overcome this problem. It is accurate by excluding the influence of impurity; it is low-cost by using common mobile phase; and it extends the applicable scope of qNMR. In this method, a mix solution of the sample and an internal standard was separated by HPLC with common mobile phases, and only the eluents of the analyte and the internal standard were collected in the same tube. After evaporation and re-dissolution, it was determined by qNMR. A recovery correction factor was determined by comparison of the solutions before and after these procedures. After correction, the mass fraction of analyte was constant and it was accurate and precise, even though the sample loss varied during these procedures, or even in bad resolution of HPLC. Avermectin B 1 a with the purity of ~93% and the molecular weight of 873 was analyzed. Moreover, the homologues of avermectin B 1 a were determined based on the identification and quantitative analysis by tandem mass spectrometry and HPLC, and the results were consistent with the results of traditional mass balance method. The result showed that the method could be widely used for the organic compounds, and could further promote qNMR to become a primary method in the international metrological systems. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Nuclear quadrupole resonance of arsenolite

    International Nuclear Information System (INIS)

    Madarazo, R.

    1988-01-01

    A pulsed Nuclear Quadrupole Resonance (NQR) spectrometer was constructed using imported Matec units. Peripherical components were specially assembled and tested for the implantation of the spin-echo technique in the Laboratorio de Centros de Cor of IFUSP. The R.F. operation range is from 50 to 1 ) and spin-spin (T 2 ) relaxation times were carried out at room temperature in arsenolite. The 75 As NQR frequency measured at room temperature is 116.223 MHz. (author) [pt

  2. GHz nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Cross, T.A.; Drobny, G.; Trewhella, J.

    1994-12-01

    For the past dozen years, 500- and 600-MHz spectrometers have become available in many laboratories. The first 600-MHz NMR spectrometer (at Carnegie Mellon University) was commissioned more than 15 years ago and, until 1994, represented the highest field available for high-resolution NMR. This year, we have witnessed unprecedented progress in the development of very high field magnets for NMR spectroscopy, including the delivery of the first commercial 750-MHz NMR spectrometers. In addition, NMR signals have been obtained from 20-Tesla magnets (850 MHz for {sup 1}H`s) at both Los Alamos National Laboratory and Florida State University in the NHMFL (National High Magnetic Field Laboratory). These preliminary experiments have been performed in magnets with 100-ppm homogeneity, but a 20-Tesla magnet developed for the NHMFL will be brought to field this year with a projected homogeneity of 0.1 ppm over a 1-cm-diam spherical volume.

  3. Nuclear level mixing resonance spectroscopy

    International Nuclear Information System (INIS)

    Coussement, R.; Put, P.; Scheveneels, G.; Hardeman, F.

    1985-01-01

    The existent methods for measuring quadrupole interactions are not suited to nuclei with lifetimes in the micro-seconds to minutes region. AD/NQR, a possible candidate in this lifetime gap, has not yet succeeded in overcoming its predicted difficulties. A new resonant method, recently developed and based on the principles of level mixing (cfr atomic spectroscopy) covers this less accessible lifetime range. Many other kinds of resonances can be described according to the level mixing formalism. The particular example of NMR as a level mixing resonance (LMR) is discussed. The underlying theory of LMR and its important consequences, leading to some interesting features of the method, is briefly formulated. Two successfully performed measurements demonstrate the feasibility and the predicted characteristics of this new promising method. (orig.)

  4. Fingerprinting analysis of Rhizoma chuanxiong of commercial types using 1H nuclear magnetic resonance spectroscopy and high performance liquid chromatography method.

    Science.gov (United States)

    Qin, Hai-Lin; Deng, An-Jun; Du, Guan-Hua; Wang, Peng; Zhang, Jin-Lan; Li, Zhi-Hong

    2009-06-01

    The (1)H nuclear magnetic resonance ((1)H NMR) fingerprints of fractionated non-polar extracts (control substance for a plant drug (CSPD) A) from Rhizoma chuanxiong, the rhizomes of Ligusticum chuanxiong Hort., of seven specimens from different sources were measured on Fourier Transform (FT)-NMR spectrometer and assigned by comparing them with the (1)H NMR spectra of the isolated pure compounds. The (1)H NMR fingerprints showed exclusively characteristic resonance signals of the major special constituents of the plant. Although the differences in the relative intensity of the (1)H NMR signals due to a discrepancy in the ratio of the major constituents among these samples could be confirmed by high performance liquid chromatography analysis, the general features of the (1)H NMR fingerprint established for an authentic sample of the rhizomes of L. chuanxiong exhibited exclusive data from those special compounds and can be used for authenticating L. Chuanxiong species.

  5. Fingerprinting Analysis of Rhizoma Chuanxiong of Commercial Types using 1H Nuclear Magnetic Resonance Spectroscopy and High Performance Liquid Chromatography Method

    Institute of Scientific and Technical Information of China (English)

    Hai-Lin Qin; An-Jun Deng; Guan-Hua Du; Peng Wang; Jin-Lan Zhang; Zhi-Hong Li

    2009-01-01

    The 1H nuclear magnetic resonance (1H NMR) fingerprints of fractionated non-polar extracts (control substance for a plant drug (CSPD) A) from Rhizoma chuanxiong, the rhizomes of Ligusticum chuanxiong Hort., of seven specimens from different sources were measured on Fourier Transform (FT)-NMR spectrometer and assigned by comparing them with the 1H NMR spectra of the isolated pure compounds. The 1H NMR fingerprints showed exclusively characteristic resonance signals of the major special constituents of the plant. Although the differences in the relative intensity of the 1H NMR signals due to a discrepancy in the ratio of the major constituents among these samples could be confirmed by high performance liquid chromatography analysis, the general features of the 1H NMR fingerprint established for an authentic sample of the rhizomes of L. chuanxiong exhibited exclusive data from those special compounds and can be used for authenticating L. Chuanxiong species.

  6. Transition metal nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Pregosin, P.S.

    1991-01-01

    Transition metal NMR spectroscopy has progressed enormously in recent years. New methods, and specifically solid-state methods and new pulse sequences, have allowed access to data from nuclei with relatively low receptivities with the result that chemists have begun to consider old and new problems, previously unapproachable. Moreover, theory, computational science in particular, now permits the calculation of not just 13 C, 15 N and other light nuclei chemical shifts, but heavy main-group element and transition metals as well. These two points, combined with increasing access to high field pulsed spectrometer has produced a wealth of new data on the NMR transition metals. A new series of articles concerned with measuring, understanding and using the nuclear magnetic resonance spectra of the metals of Group 3-12 is presented. (author)

  7. The nuclear magnetic resonance well logging

    International Nuclear Information System (INIS)

    Zhang Yumin; Shen Huitang

    2003-01-01

    In this paper, the characteristic of the nuclear magnetic resonance logging is described at first. Then its development and its principle is presented. Compared with the nuclear magnetic resonance spectrometer, the magnet techniques is the first question that we must solve in the manufacture of the NMR well logging

  8. Nuclear magnetic resonance imaging method

    International Nuclear Information System (INIS)

    Johnson, G.; MacDonald, J.; Hutchison, S.; Eastwood, L.M.; Redpath, T.W.T.; Mallard, J.R.

    1984-01-01

    A method of deriving three dimensional image information from an object using nuclear magnetic resonance signals comprises subjecting the object to a continuous, static magnetic field and carrying out the following set of sequential steps: 1) exciting nuclear spins in a selected volume (90deg pulse); 2) applying non-aligned first, second and third gradients of the magnetic field; 3) causing the spins to rephase periodically by reversal of the first gradient to produce spin echoes, and applying pulses of the second gradient prior to every read-out of an echo signal from the object, to differently encode the spin in the second gradient direction for each read-out signal. The above steps 1-3 are then successively repeated with different values of gradient of the third gradient, there being a recovery interval between the repetition of successive sets of steps. Alternate echoes only are read out, the other echoes being time-reversed and ignored for convenience. The resulting signals are appropriately sampled, set out in an array and subjected to three dimensional Fourier transformation. (author)

  9. Fifty years of nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Martinez Valderrama, Juan Crisostomo

    1997-01-01

    Short information about the main developments of nuclear magnetic resonance during their fifty existence years is presented. Beside two examples of application (HETCOR and INADEQUATE) to the structural determination of organic compounds are described

  10. Principles of nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Pykett, I.L.; Newhouse, J.H.; Buonanno, F.S.; Brady, T.J.; Goldman, M.R.; Kistler, J.P.; Pohost, G.M.

    1982-01-01

    The physical principles which underlie the phenomenon of nuclear magnetic resonance (NMR) are presented in this primer. The major scanning methods are reviewed, and the principles of technique are discussed. A glossary of NMR terms is included

  11. Nuclear Magnetic Resonance Trackbed Moisture Sensor System

    Science.gov (United States)

    2018-02-01

    In this initial phase, conducted from March 2015 through December 2016, Vista Clara and its subcontractor Zetica Rail successfully developed and tested a man-portable, non-invasive spot-check nuclear magnetic resonance (NMR) moisture sensor that dire...

  12. Sensitivity enhancement by chromatographic peak concentration with ultra-high performance liquid chromatography-nuclear magnetic resonance spectroscopy for minor impurity analysis.

    Science.gov (United States)

    Tokunaga, Takashi; Akagi, Ken-Ichi; Okamoto, Masahiko

    2017-07-28

    High performance liquid chromatography can be coupled with nuclear magnetic resonance (NMR) spectroscopy to give a powerful analytical method known as liquid chromatography-nuclear magnetic resonance (LC-NMR) spectroscopy, which can be used to determine the chemical structures of the components of complex mixtures. However, intrinsic limitations in the sensitivity of NMR spectroscopy have restricted the scope of this procedure, and resolving these limitations remains a critical problem for analysis. In this study, we coupled ultra-high performance liquid chromatography (UHPLC) with NMR to give a simple and versatile analytical method with higher sensitivity than conventional LC-NMR. UHPLC separation enabled the concentration of individual peaks to give a volume similar to that of the NMR flow cell, thereby maximizing the sensitivity to the theoretical upper limit. The UHPLC concentration of compound peaks present at typical impurity levels (5.0-13.1 nmol) in a mixture led to at most three-fold increase in the signal-to-noise ratio compared with LC-NMR. Furthermore, we demonstrated the use of UHPLC-NMR for obtaining structural information of a minor impurity in a reaction mixture in actual laboratory-scale development of a synthetic process. Using UHPLC-NMR, the experimental run times for chromatography and NMR were greatly reduced compared with LC-NMR. UHPLC-NMR successfully overcomes the difficulties associated with analyses of minor components in a complex mixture by LC-NMR, which are problematic even when an ultra-high field magnet and cryogenic probe are used. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Nuclear magnetic resonance studies of lens transparency

    International Nuclear Information System (INIS)

    Beaulieu, C.F.

    1989-01-01

    Transparency of normal lens cytoplasm and loss of transparency in cataract were studied by nuclear magnetic resonance (NMR) methods. Phosphorus ( 31 P) NMR spectroscopy was used to measure the 31 P constituents and pH of calf lens cortical and nuclear homogenates and intact lenses as a function of time after lens enucleation and in opacification produced by calcium. Transparency was measured with laser spectroscopy. Despite complete loss of adenosine triphosphate (ATP) within 18 hrs of enucleation, the homogenates and lenses remained 100% transparent. Additions of calcium to ATP-depleted cortical homogenates produced opacification as well as concentration-dependent changes in inorganic phosphate, sugar phosphates, glycerol phosphorylcholine and pH. 1 H relaxation measurements of lens water at 200 MHz proton Larmor frequency studied temperature-dependent phase separation of lens nuclear homogenates. Preliminary measurements of T 1 and T 2 with non-equilibrium temperature changes showed a change in the slope of the temperature dependence of T 1 and T 2 at the phase separation temperature. Subsequent studies with equilibrium temperature changes showed no effect of phase separation on T 1 or T 2 , consistent with the phase separation being a low-energy process. 1 H nuclear magnetic relaxation dispersion (NMRD) studies (measurements of the magnetic field dependence of the water proton 1/T 1 relaxation rates) were performed on (1) calf lens nuclear and cortical homogenates (2) chicken lens homogenates, (3) native and heat-denatured egg white and (4) pure proteins including bovine γ-II crystallin bovine serum albumin (BSA) and myoglobin. The NMRD profiles of all samples exhibited decreases in 1/T 1 with increasing magnetic field

  14. Comparison of nuclear electric resonance and nuclear magnetic resonance in integer and fractional quantum Hall states

    International Nuclear Information System (INIS)

    Tomimatsu, Toru; Shirai, Shota; Hashimoto, Katsushi; Sato, Ken; Hirayama, Yoshiro

    2015-01-01

    Electric-field-induced nuclear resonance (NER: nuclear electric resonance) involving quantum Hall states (QHSs) was studied at various filling factors by exploiting changes in nuclear spins polarized at quantum Hall breakdown. Distinct from the magnetic dipole interaction in nuclear magnetic resonance, the interaction of the electric-field gradient with the electric quadrupole moment plays the dominant role in the NER mechanism. The magnitude of the NER signal strongly depends on whether electronic states are localized or extended. This indicates that NER is sensitive to the screening capability of the electric field associated with QHSs

  15. Nuclear magnetic resonance method and apparatus

    International Nuclear Information System (INIS)

    Burl, M.; Young, I.R.

    1984-01-01

    A method and apparatus for determining the rate of flow of a liquid in a selected region of a body by nuclear magnetic resonance techniques are described. The method includes a sequence of applying a first magnetic pulse effective to excite nuclear magnetic resonance of a chosen nucleus within the liquid preferentially in a slice of the body which includes the selected region. A period of time (tsub(D)) is waited and then a second magnetic pulse is applied which is effective to excite nuclear magnetic resonance of the nuclei preferentially in the slice, and the free induction decay signal is measured. The whole sequence is repeated for different values of the period of time (tsub(D)). The variation in the value of the measured signal with tsub(D) is then related to the rate of flow of the liquid through the slice. (author)

  16. Nuclear magnetic resonance spectroscopy and imaging

    International Nuclear Information System (INIS)

    Jiang Weiping; Wang Qi; Zhou Xin

    2013-01-01

    This paper briefly introduces the basic principle of nuclear magnetic resonance (NMR). Protein's structures and functions and dynamics studied by liquid NMR are elaborated; methods for enhancing the resolution of solid state NMR and its applications are discussed; the principle of magnetic resonance imaging (MRI) is interpreted, and applications in different aspects are reviewed. Finally, the progress of NMR is commented. (authors)

  17. Nuclear performance and reliability

    International Nuclear Information System (INIS)

    Rothwell, G.

    1993-01-01

    If fewer forced outages are a sign of improved safety, nuclear power plants have become safer and more productive. There has been a significant improvement in nuclear power plant performance, due largely to a decline in the forced outage rate and a dramatic drop in the average number of forced outages per fuel cycle. If fewer forced outages are a sign of improved safety, nuclear power plants have become safer and more productive over time. To encourage further increases in performance, regulatory incentive schemes should reward reactor operators for improved reliability and safety, as well as for improved performance

  18. Nuclear Resonance Fluorescence for Safeguards Applications

    Energy Technology Data Exchange (ETDEWEB)

    Ludewigt, Bernhard A; Quiter, Brian J; Ambers, Scott D

    2011-02-04

    In nuclear resonance fluorescence (NRF) measurements, resonances are excited by an external photon beam leading to the emission of {gamma} rays with specific energies that are characteristic of the emitting isotope. The promise of NRF as a non-destructive analysis technique (NDA) in safeguards applications lies in its potential to directly quantify a specific isotope in an assay target without the need for unfolding the combined responses of several fissile isotopes as often required by other NDA methods. The use of NRF for detection of sensitive nuclear materials and other contraband has been researched in the past. In the safeguards applications considered here one has to go beyond mere detection and precisely quantify the isotopic content, a challenge that is discussed throughout this report. Basic NRF measurement methods, instrumentation, and the analytical calculation of NRF signal strengths are described in Section 2. Well understood modeling and simulation tools are needed for assessing the potential of NRF for safeguards and for designing measurement systems. All our simulations were performed with the radiation transport code MCNPX, a code that is widely used in the safeguards community. Our initial studies showed that MCNPX grossly underestimated the elastically scattered background at backwards angles due to an incorrect treatment of Rayleigh scattering. While new, corrected calculations based on ENDF form factors showed much better agreement with experimental data for the elastic scattering of photons on an uranium target, the elastic backscatter is still not rigorously treated. Photonuclear scattering processes (nuclear Thomson, Delbruck and Giant Dipole Resonance scattering), which are expected to play an important role at higher energies, are not yet included. These missing elastic scattering contributions were studied and their importance evaluated evaluated against data found in the literature as discussed in Section 3. A transmission experiment

  19. Force detection of nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Rugar, D.; Zueger, O.; Hoen, S.; Yannoni, C.S.; Vieth, H.M.; Kendrick, R.D.

    1994-01-01

    Micromechanical sensing of magnetic force was used to detect nuclear magnetic resonance with exceptional sensitivity and spatial resolution. With a 900 angstrom thick silicon nitride cantilever capable of detecting subfemtonewton forces, a single shot sensitivity of 1.6 x 10 13 protons was achieved for an ammonium nitrate sample mounted on the cantilever. A nearby millimeter-size iron particle produced a 600 tesla per meter magnetic field gradient, resulting in a spatial resolution of 2.6 micrometers in one dimension. These results suggest that magnetic force sensing is a viable approach for enhancing the sensitivity and spatial resolution of nuclear magnetic resonance microimaging

  20. Basis of the nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Bahceli, S.

    1996-08-01

    The aim of this book which is translated from English language is to explain the physical and mathematical basis of nuclear magnetic resonance (NMR). There are nine chapters covering different aspects of NMR. In the firs chapter fundamental concepts of quantum mechanics are given at a level suitable for readers to understand NMR fully. The remaining chapters discuss the magnetic properties of nucleus, the interactions between atoms and molecules, continuous wave NMR, pulsed NMR, nuclear magnetic relaxation and NMR of liquids

  1. Nuclear disarmament verification via resonant phenomena.

    Science.gov (United States)

    Hecla, Jake J; Danagoulian, Areg

    2018-03-28

    Nuclear disarmament treaties are not sufficient in and of themselves to neutralize the existential threat of the nuclear weapons. Technologies are necessary for verifying the authenticity of the nuclear warheads undergoing dismantlement before counting them toward a treaty partner's obligation. Here we present a concept that leverages isotope-specific nuclear resonance phenomena to authenticate a warhead's fissile components by comparing them to a previously authenticated template. All information is encrypted in the physical domain in a manner that amounts to a physical zero-knowledge proof system. Using Monte Carlo simulations, the system is shown to reveal no isotopic or geometric information about the weapon, while readily detecting hoaxing attempts. This nuclear technique can dramatically increase the reach and trustworthiness of future nuclear disarmament treaties.

  2. Atomic resonances in nuclear fusion plasmas

    International Nuclear Information System (INIS)

    Clauser, C. F.; Barrachina, R. O.

    2013-01-01

    We present a study of zero energy resonances of photoionization and radiative recombination cross section for the different species in a fusion reactor. In this context, the interaction potential is screened and its typical length depends on the plasma density and temperature. Due to the nature of these resonances, we propose other atomic processes in which they can take place. Finally, we show the density and temperature conditions where these resonances occur and their probable consequence on the reactor performance. (author)

  3. Resonances: from nuclear physics to mesoscopic systems

    International Nuclear Information System (INIS)

    Ferreira, Lidia S.; Maglione, Enrico

    2007-01-01

    Resonances are one of the most interesting phenomena in many fields of physics which lead to important findings. In the quantum world, systems with electrons, hadrons or atoms provide enormous amount of data on resonances, leading to the discovery of new states of matter. In nuclear physics, the recent findings on exotic nuclei, added to the list many new examples, which are important not only as direct data on resonances, but also for the production of new isotopes in regions of the nuclear chart which were 'terra incognita', until recently. With recent developments in microelectronics it is possible to create in the laboratory almost two dimensional wave guides where the motion of the electrons can exhibit typical quantum effects. The geometry of systems, such as bends, corners or crosses, has a strong influence on the conduction properties of the electrons, since it can create the appropriate conditions required for the formation of bound states or resonances in the conduction channels. Therefore it is quite important to have an accurate description of the relation between geometry and observables, which in a theoretical perspective emerges naturally from the solution of a multichannel eigenvalue problem. The study of resonances and their behaviour in these domains of physics, will be the purpose of the lecture. (Author)

  4. Two qubits in pure nuclear quadrupole resonance

    International Nuclear Information System (INIS)

    Furman, G.B.; Goren, S.D.; Meerovich, V.M.; Sokolovsky, V.L.

    2002-01-01

    It is shown theoretically that by the use of two radio-frequency fields of the same resonance frequency but with the different phases and directions the degeneracy of the energy spectrum of a spin system with I=3/2 is removed. This leads to four non-degenerate spin states which can be used as a platform for quantum computing. The feasibility of quantum computing based on a pure (without DC magnetic fields) nuclear quadrupole resonance technique is investigated in detail. Various quantum logic gates can be constructed by using different excitation techniques allowing different manipulations with the spin system states. Three realizations of quantum logic gates are considered: the application of an additional magnetic field with the resonance frequency, the amplitude modulation of one of the applied RF fields by the resonance frequency field, and the level-crossing method. It is shown that the probabilities of the resonance transitions depend on the method of excitation and on the direction of the excitation field. Feasibility of quantum computing is demonstrated with the examples of constructing a controlled-NOT logic gate using the resonance excitation technique and SWAP and NOT2 logic gates using the level-crossing method. (author)

  5. Nuclear magnetic resonance and high-performance liquid chromatography techniques for the characterization of bioactive compounds from Humulus lupulus L. (hop).

    Science.gov (United States)

    Bertelli, Davide; Brighenti, Virginia; Marchetti, Lucia; Reik, Anna; Pellati, Federica

    2018-06-01

    Humulus lupulus L. (hop) represents one of the most cultivated crops, it being a key ingredient in the brewing process. Many health-related properties have been described for hop extracts, making this plant gain more interest in the field of pharmaceutical and nutraceutical research. Among the analytical tools available for the phytochemical characterization of plant extracts, quantitative nuclear magnetic resonance (qNMR) represents a new and powerful technique. In this ambit, the present study was aimed at the development of a new, simple, and efficient qNMR method for the metabolite fingerprinting of bioactive compounds in hop cones, taking advantage of the novel ERETIC 2 tool. To the best of our knowledge, this is the first attempt to apply this method to complex matrices of natural origin, such as hop extracts. The qNMR method set up in this study was applied to the quantification of both prenylflavonoids and bitter acids in eight hop cultivars. The performance of this analytical method was compared with that of HPLC-UV/DAD, which represents the most frequently used technique in the field of natural product analysis. The quantitative data obtained for hop samples by means of the two aforementioned techniques highlighted that the amount of bioactive compounds was slightly higher when qNMR was applied, although the order of magnitude of the values was the same. The accuracy of qNMR was comparable to that of the chromatographic method, thus proving to be a reliable tool for the analysis of these secondary metabolites in hop extracts. Graphical abstract Graphical abstract related to the extraction and analytical methods applied in this work for the analysis of bioactive compounds in Humulus lupulus L. (hop) cones.

  6. Nonlinear nuclear magnetic resonance in ferromagnets

    International Nuclear Information System (INIS)

    Nurgaliev, T.

    1988-01-01

    The properties of nonlinear nuclear magnetic resonance (NMR) have been studied theoretically by taking into account the interaction between NMR and FMR in the ferromagnets. The Landau-Lifshitz-Bloch equations, describing the electron and nuclear magnetization behaviour in ferromagnets are presented in an integral form for a weakly excited electronic system. The stationary solution of these equations has been analysed in the case of equal NMR and FMR frequencies: the criteria for the appearance of two stable dynamic states is found and the high-frequency magnetic susceptibility for these systems is investigated. 2 figs., 8 refs

  7. Nuclear magnetic resonance and medicine. Present applications

    International Nuclear Information System (INIS)

    1984-01-01

    At the workshop on nuclear magnetic resonance and medicine held at Saclay, the following topics were presented: physical principles of NMR; NMR spectroscopy signal to noise ratio; principles of NMR imaging; methods of NMR imaging; image options in NMR; biological significance of contrast in proton NMR imaging; measurement and significance of relaxation times in cancers; NMR contrast agents; NMR for in-vivo biochemistry; potential effects and hazards of NMR applications in Medicine; difficulties of NMR implantation in Hospitals; NMR imaging of brain tumors and diseases of the spinal cord; NMR and Nuclear Medicine in brain diseases [fr

  8. Two-dimensional nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Bax, A.; Lerner, L.

    1986-01-01

    Great spectral simplification can be obtained by spreading the conventional one-dimensional nuclear magnetic resonance (NMR) spectrum in two independent frequency dimensions. This so-called two-dimensional NMR spectroscopy removes spectral overlap, facilitates spectral assignment, and provides a wealth of additional information. For example, conformational information related to interproton distances is available from resonance intensities in certain types of two-dimensional experiments. Another method generates 1 H NMR spectra of a preselected fragment of the molecule, suppressing resonances from other regions and greatly simplifying spectral appearance. Two-dimensional NMR spectroscopy can also be applied to the study of 13 C and 15 N, not only providing valuable connectivity information but also improving sensitivity of 13 C and 15 N detection by up to two orders of magnitude. 45 references, 10 figures

  9. Nuclear magnetic resonance - from molecules to man

    OpenAIRE

    Wüthrich, Kurt

    2017-01-01

    Initial observations of the physical phenomenon of nuclear magnetic resonance (NMR) date back to the late 1940s. In the following two decades high-resolution NMR in solution became an indispensible analytical tool in chemistry, and solid state NMR had an increasingly important role in physics. Some of the potentialities of the method for investigations of complex biological systems had also long been anticipated, and initial experiments with biological specimens were described already 30 year...

  10. Nuclear magnetic resonance (NMR): principles and applications

    International Nuclear Information System (INIS)

    Quibilan, E.I.

    The basis for the phenomenon of nuclear magnetic resonance (NMR) is the ability of certain nuclei possessing both intrinsic angular momentum or ''spin'' I and magnetic moment to absorb electromagnetic energy in the radio frequency range. In principle, there are approximately 200 nuclei which may be investigated using the NMR technique. The NMR spectrum consists of intensity peaks along an axis calibrated in terms of the steady magnetic field or the frequency of the radiofrequency electromagnetic radiation. Analysis of the number, spacing, position and intensity of the lines in an NMR spectrum consists of intensity peaks along an axis calibrated in terms of the steady magnetic field or the frequency of the radiofrequency electromagnetic radiation. Analysis of the number, spacing, position and intensity of the lines in an NMR spectrum provides a variety of qualitative and quantitative analytical applications. The most obvious applications consist of the measurements of nuclear properties, such as spin number and nuclear magnetic moment. In liquids, the fine structure of resonance spectra provides a tool for chemical identification and molecular structure analysis. Other applications include the measurements of self-diffusion coefficients, magnetic fields and field homogeneity, inter-nuclear distances, and, in some cases, the water content of biological materials. (author)

  11. Good performance in nuclear projects

    International Nuclear Information System (INIS)

    1989-01-01

    The nuclear industry has demonstrated good performance in many areas relating to the design, engineering, construction and operation of nuclear facilities. This report of an international symposium held in Tokyo highlights examples of good performance in nuclear projects which can aid the industry in seeking even better performance, thus strengthening the contribution nuclear energy can make to sustainable economic growth

  12. Clinical applications of nuclear magnetic resonance spectroscopy: a review

    International Nuclear Information System (INIS)

    Newman, R.J.

    1984-01-01

    The advantages and present limitations of the clinical applications of nuclear magnetic resonance spectroscopy are reviewed in outline, with passing references to skeletal muscular studies, in particular a group of children with advanced Duchenne dystrophy, and the applications to the study of cerebral metabolism of neonates, excised kidneys, biopsy studies of breast and axillary lymph node samples, and NMR spectroscopy performed during chemotherapy of a secondary rhabdomyosarcoma in the skin. (U.K.)

  13. Clinical applications of nuclear magnetic resonance spectroscopy: a review

    Energy Technology Data Exchange (ETDEWEB)

    Newman, R.J. (Glasgow Western Infirmary (UK))

    1984-09-01

    The advantages and present limitations of the clinical applications of nuclear magnetic resonance spectroscopy are reviewed in outline, with passing references to skeletal muscular studies, in particular a group of children with advanced Duchenne dystrophy, and the applications to the study of cerebral metabolism of neonates, excised kidneys, biopsy studies of breast and axillary lymph node samples, and NMR spectroscopy performed during chemotherapy of a secondary rhabdomyosarcoma in the skin.

  14. Nuclear magnetic resonance studies of epithelial metabolism and function

    International Nuclear Information System (INIS)

    Balaban, R.S.

    1982-01-01

    Nuclear magnetic resonance (NMR) is a noninvasive technique for studying cellular metabolism and function. In this review the general applications and advantages of NMR will be discussed with specific reference to epithelial tissues. Phosphorus NMR investigations have been performed on epithelial tissues in vivo and in vitro; however, other detectable nuclei have not been utilized to date. Several new applications of phosphorus NMR to epithelial tissues are also discussed, including studies on isolated renal tubules and sheet epithelia

  15. Quantitative dosing by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Solomon, I.

    1958-01-01

    The measurement of the absolute concentration of a heavy water reference containing approximately 99.8 per cent of D 2 O has been performed, by an original magnetic resonance method ('Adiabatic fast passage method') with a precision of 5.10 -5 on the D 2 O concentration. (author) [fr

  16. Nuclear magnetic resonance imaging in pharmaceutical research

    International Nuclear Information System (INIS)

    Sarkar, S.K.

    1991-01-01

    Nuclear magnetic resonance imaging has important applications in pharmaceutical research since it allows specific tissue and disease characterization in animal models noninvasively with excellent anatomical resolution and therefore provides improved ability to monitor the efficacy of novel drugs. The utility of NMR imaging in renal studies to monitor the mechanism of drug action and renal function in rats is described. The extension of the resolution of an NMR image to microscopic domain at higher magnetic field strengths and the utility of NMR microimaging in cerebrovascular and tumour metastasis studies in mice are discussed. (author). 40 refs., 14 figs

  17. Nuclear magnetic resonance common laboratory, quadrennial report

    International Nuclear Information System (INIS)

    1994-01-01

    This quadrennial report of the nuclear magnetic resonance common laboratory gives an overview of the main activities. Among the different described activities, only one is interesting for the INIS database: it concerns the Solid NMR of cements used for radioactive wastes storage. In this case, the NMR is used to characterize the structure of the material and the composition, structure and kinetics of formation of the alteration layer which is formed at the surface of concrete during water leaching conditions. The NMR methodology is given. (O.M.)

  18. Nuclear magnetic resonance applications in biological systems

    International Nuclear Information System (INIS)

    Jiang Ling; Liu Maili

    2011-01-01

    Nuclear magnetic resonance (NMR) spectroscopy is a state-of-the-art technology which has been widely applied in biological systems over the past decades. It is a powerful tool for macromolecular structure determination in solution, and has the unique advantage of being capable of elucidating the structure and dynamic behavior of proteins during vital biomedical processes. In this review, we introduce the recent progress in NMR techniques for studying the structure, interaction and dynamics of proteins. The methods for NMR based drug discovery and metabonomics are also briefly introduced. (authors)

  19. Generation of nuclear magnetic resonance images

    International Nuclear Information System (INIS)

    Beckmann, N.X.

    1986-01-01

    Two generation techniques of nuclear magnetic resonance images, the retro-projection and the direct transformation method are studied these techniques are based on the acquisition of NMR signals which phases and frequency components are codified in space by application of magnetic field gradients. The construction of magnet coils is discussed, in particular a suitable magnet geometry with polar pieces and air gap. The obtention of image contrast by T1 and T2 relaxation times reconstructed from generated signals using sequences such as spin-echo, inversion-recovery and stimulated echo, is discussed. The mathematical formalism of matrix solution for Bloch equations is also presented. (M.C.K.)

  20. Nuclear magnetic resonance method and apparatus

    International Nuclear Information System (INIS)

    Young, I.R.

    1983-01-01

    In a method of investigating the distribution of a quantity in a chosen region of a body (E) by nuclear magnetic resonance techniques movement of the body during the investigation is monitored by probes (A, B C) (C extends orthogonally to A and B) attached to the body and responsive to magnetic fields applied to the body during the investigation. An apparatus for carrying out the method is also described. If movement is detected, due compensation may be made during processing of the collected data, or the latter may be re-ascertained after appropriate adjustment e.g. a change in the RF excitation frequency. (author)

  1. Fast storage of nuclear quadrupole resonance signals

    International Nuclear Information System (INIS)

    Anferov, V.P.; Molchanov, S.V.; Levchun, O.D.

    1988-01-01

    Fast multichannel storage of nuclear quadrupole resonance (NQR) signals is described. Analog-to-digital converter, arithmetic-logical unit, internal memory device (IMD) selection-storage unit and control unit are the storage main units. The storage is based on 43 microcircuits and provides for record and storage of NQR-signals at the contributed operation with Mera-60 microcomputer. Time of analog-to-digital conversion and signal recording into IMD is ∼ 1 mks. Capacity of analog-to-digital converter constitutes 8-10 bits. IMD capacity is 4 K bitsx16. Number of storage channels is 4

  2. Nuclear magnetic resonance and earth magnetic field

    International Nuclear Information System (INIS)

    Anon.

    1998-01-01

    Nuclear magnetic resonance concerns nuclei whose spin is different from 0. These nuclei exposed to a magnetic field is comparable to a peg top spinning around its axis while being moved by a precession movement called Larmor precession. This article presents an experiment whose aim is to reveal nuclear magnetism of nuclei by observing Larmor precession phenomena due to the earth magnetic field. The earth magnetic field being too weak, it is necessary to increase the magnetization of the sample during a polarization phase. First the sample is submitted to a magnetic field B perpendicular to the earth magnetic field B 0 , then B is cut off and the nuclei move back to their equilibrium position by executing a precession movement due to B 0 field. (A.C.)

  3. Nuclear magnetic resonance in ferromagnetic terbium metal

    International Nuclear Information System (INIS)

    Cha, C.L.T.

    1974-01-01

    The magnetic properties of terbium were studied by the method of zero field nuclear magnetic resonance at 1.5 to 4 and 85 to 160 0 K. Two unconventional experimental techniques have been employed: the swept frequency and the swept temperature technique. Near 4 0 K, triplet resonance line structures were found and interpreted in terms of the magnetic domain and wall structures of ferromagnetic terbium. In the higher temperature range, temperature dependence of the resonance frequency and the quadrupole splitting were measured. The former provides a measurement of the temperature dependence of the magnetization M, and it agrees with bulk M measurements as well as the latest spin wave theory of M(T) (Brooks 1968). The latter agrees well with a calculation using a very general single ion density matrix for collective excitations (Callen and Shtrikman 1965). In addition, the small temperature-independent contribution to the electric field gradient at the nucleus due to the lattice and conduction electrons was untangled from the P(T) data. Also an anomalous and unexplained relaxation phenomenon was also observed

  4. High resolution spectroscopy in solids by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Bonagamba, T.J.

    1991-07-01

    The nuclear magnetic resonance (NMR) techniques for High Resolution Spectroscopy in Solids are described. Also the construction project of a partially home made spectrometer and its applications in the characterization of solid samples are shown in detail. The high resolution spectrometer used is implemented with the double resonance multiple pulses sequences and magic angle spinning (MAS) and can be used with solid and liquid samples. The maximum spinning frequency for the MAS experiment is in excess of 5 Khz, the double resonance sequences can be performed with any type of nucleus, in the variable temperature operating range with nitrogen gas: -120 0 C to +160 0 C, and is fully controlled by a Macintosh IIci microcomputer. (author)

  5. Nuclear magnetic resonance spectroscopy in organic chemistry. 2. ed.

    International Nuclear Information System (INIS)

    Zschunke, A.

    1977-01-01

    The fundamentals of nuclear magnetic resonance spectroscopy are discussed only briefly. The emphasis is laid on developing reader's ability to evaluate resonance spectra. The following topics are covered: principles of nuclear magnetic resonance spectroscopy; chemical shift and indirect nuclear spin coupling constants and their relation to the molecular structure; analysis of spectra; and uses for structural analysis and solution of kinetic problems, mainly with regard to organic compounds. Of interest to chemists and graduate students who want to make themselves acquainted with nuclear magnetic resonance spectroscopy

  6. Targeting high-performance liquid chromatography-high-resolution mass spectrometry-solid-phase extraction-nuclear magnetic resonance analysis with high-resolution radical scavenging profiles - bioactive secondary metabolites from the endophytic fungus Penicillium namyslowskii

    DEFF Research Database (Denmark)

    Wubshet, Sileshi Gizachew; Nyberg, Nils; Tejesvi, Mysore V.

    2013-01-01

    The high-resolution radical scavenging profile of an extract of the endophytic fungus Penicillium namyslowskii was used to target analysis by high-performance liquid chromatography-high-resolution mass spectrometry-solid-phase extraction-nuclear magnetic resonance spectroscopy, i.e., HPLC...... NMR probe designed for 1.7-mm NMR tubes. To further explore the potential of the above HPLC-HRMS-SPE-NMR platform for analysis of endophytic extracts, six peaks displaying no radical scavenging activity were also analyzed. This allowed unambiguous identification of six metabolites, i...... and griseofulvin, directly from crude extract via HPLC-HRMS-SPE-NMR. Dechlorodehydrogriseofulvin was reported for the first time from nature....

  7. Nuclear magnetic resonance imaging of the thorax

    International Nuclear Information System (INIS)

    Gamsu, G.; Webb, W.R.; Sheldon, P.; Kaufman, L.; Crooks, L.E.; Birnberg, F.A.; Goodman, P.; Hinchcliffe, W.A.; Hedgecock, M.

    1983-01-01

    Nuclear magnetic resonance (NMR) images of the thorax were obtained in ten normal volunteers, nine patients with advanced bronchogenic carcinoma, and three patients with benign thoracic abnormalities. In normal volunteers, mediastinal and hilar structures were seen with equal frequency on NMR images and computed tomographic scans. The hila were especially well displayed on spin-echo images. Spin-echo images showed mediastinal invasion by tumor, vascular and bronchial compression and invasion, and hilar and mediastinal adenopathy. Tumor and benign abnormalities could be separated from mediastinal and hilar fat because of their longer T1 times. Lung masses and nodules as small as 1.5 cm could be seen on the spin-echo images. NMR imaging shows promise for assessment of benign and malignant mediastinal, hilar, and lung abnormalities

  8. Geochemical Controls on Nuclear Magnetic Resonance Measurements

    International Nuclear Information System (INIS)

    Knight, Rosemary; Prasad, Manika; Keating, Kristina

    2003-01-01

    OAK-B135 Our research objectives are to determine, through an extensive set of laboratory experiments, the effect of the specific mineralogic form of iron and the effect of the distribution of iron on proton nuclear magnetic resonance (NMR) relaxation mechanisms. In the first nine months of this project, we have refined the experimental procedures to be used in the acquisition of the laboratory NMR data; have ordered, and conducted preliminary measurements on, the sand samples to be used in the experimental work; and have revised and completed the theoretical model to use in this project. Over the next year, our focus will be on completing the first phase of the experimental work where the form and distribution of the iron in the sands in varied

  9. Selectivity in multiple quantum nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Warren, W.S.

    1980-11-01

    The observation of multiple-quantum nuclear magnetic resonance transitions in isotropic or anisotropic liquids is shown to give readily interpretable information on molecular configurations, rates of motional processes, and intramolecular interactions. However, the observed intensity of high multiple-quantum transitions falls off dramatically as the number of coupled spins increases. The theory of multiple-quantum NMR is developed through the density matrix formalism, and exact intensities are derived for several cases (isotropic first-order systems and anisotropic systems with high symmetry) to shown that this intensity decrease is expected if standard multiple-quantum pulse sequences are used. New pulse sequences are developed which excite coherences and produce population inversions only between selected states, even though other transitions are simultaneously resonant. One type of selective excitation presented only allows molecules to absorb and emit photons in groups of n. Coherent averaging theory is extended to describe these selective sequences, and to design sequences which are selective to arbitrarily high order in the Magnus expansion. This theory and computer calculations both show that extremely good selectivity and large signal enhancements are possible

  10. Selectivity in multiple quantum nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Warren, Warren Sloan [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division

    1980-11-01

    The observation of multiple-quantum nuclear magnetic resonance transitions in isotropic or anisotropic liquids is shown to give readily interpretable information on molecular configurations, rates of motional processes, and intramolecular interactions. However, the observed intensity of high multiple-quantum transitions falls off dramatically as the number of coupled spins increases. The theory of multiple-quantum NMR is developed through the density matrix formalism, and exact intensities are derived for several cases (isotropic first-order systems and anisotropic systems with high symmetry) to shown that this intensity decrease is expected if standard multiple-quantum pulse sequences are used. New pulse sequences are developed which excite coherences and produce population inversions only between selected states, even though other transitions are simultaneously resonant. One type of selective excitation presented only allows molecules to absorb and emit photons in groups of n. Coherent averaging theory is extended to describe these selective sequences, and to design sequences which are selective to arbitrarily high order in the Magnus expansion. This theory and computer calculations both show that extremely good selectivity and large signal enhancements are possible.

  11. Evaluation and analysis of nuclear resonance data

    International Nuclear Information System (INIS)

    Frohner, F.H.

    2000-01-01

    A probabilistic foundations of data evaluation are reviewed, with special emphasis on parameter estimation based on Bayes' theorem and a quadratic loss function, and on modern methods for the assignment of prior probabilities. The data reduction process leading from raw experimental data to evaluated computer files of nuclear reaction cross sections is outlined, with a discussion of systematic and statistical errors and their propagation and of the generalized least squares formalism including prior information and nonlinear theoretical models. It is explained how common errors induce correlations between data, what consequences they have for uncertainty propagation and sensitivity studies, and how evaluators can construct covariance matrices from the usual error information provided by experimentalists. New techniques for evaluation of inconsistent data are also presented. The general principles are then applied specifically to the analysis and evaluation of neutron resonance data in terms of theoretical models - R-matrix theory (and especially its practically used multi-level Breit-Wigner and Reich-Moore variants) in the resolved region, and resonance-averaged R-matrix theory (Hauser-Feshbach theory with width-fluctuation corrections) in the unresolved region. Complications arise because the measured transmission data, capture and fission yields, self-indication ratios and other observables are not yet the wanted cross sections. These are obtained only by means of parametrisation. The intervening effects - Doppler and resolution broadening, self-shielding, multiple scattering, backgrounds, sample impurities, energy-dependent detector efficiencies, inaccurate reference data etc - are therefore also discussed. (author)

  12. Diagnostic apparatus employing nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Hoshino, K.; Yamada, N.; Yoshitome, E.; Matsuura, H.

    1987-01-01

    An NMR diagnostic apparatus is described comprising means for applying a primary magnetic field to a subject; means for applying RF pulses to the subject to give nuclear magnetic resonance to the nuclei of atoms in the subject; means for applying gradient magnetic fields to project an NMR signal of the nuclei at least in one direction; means for observing the NMR signal projected by the gradient magnetic fields applying means; and arithmetic means for constructing a distribution of information on resonance energy as an image from an output signal from the observing means; wherein the gradient magnetic fields applying means comprises means for applying the gradient magnetic fields at a predetermined time and for not applying the gradient magnetic fields at another predetermined time, during the time period of one view; and wherein the gradient magnetic fields applying means further comprises means for measuring the NMR signal during the predetermined time when the gradient magnetic fields are applied, and means for measuring the intensity of the primary magnetic field during the other predetermined time when no gradient magnetic fields are applied

  13. On-line high-performance liquid chromatography-ultraviolet-nuclear magnetic resonance method of the markers of nerve agents for verification of the Chemical Weapons Convention.

    Science.gov (United States)

    Mazumder, Avik; Gupta, Hemendra K; Garg, Prabhat; Jain, Rajeev; Dubey, Devendra K

    2009-07-03

    This paper details an on-flow liquid chromatography-ultraviolet-nuclear magnetic resonance (LC-UV-NMR) method for the retrospective detection and identification of alkyl alkylphosphonic acids (AAPAs) and alkylphosphonic acids (APAs), the markers of the toxic nerve agents for verification of the Chemical Weapons Convention (CWC). Initially, the LC-UV-NMR parameters were optimized for benzyl derivatives of the APAs and AAPAs. The optimized parameters include stationary phase C(18), mobile phase methanol:water 78:22 (v/v), UV detection at 268nm and (1)H NMR acquisition conditions. The protocol described herein allowed the detection of analytes through acquisition of high quality NMR spectra from the aqueous solution of the APAs and AAPAs with high concentrations of interfering background chemicals which have been removed by preceding sample preparation. The reported standard deviation for the quantification is related to the UV detector which showed relative standard deviations (RSDs) for quantification within +/-1.1%, while lower limit of detection upto 16mug (in mug absolute) for the NMR detector. Finally the developed LC-UV-NMR method was applied to identify the APAs and AAPAs in real water samples, consequent to solid phase extraction and derivatization. The method is fast (total experiment time approximately 2h), sensitive, rugged and efficient.

  14. Nuclear elasticity applied to giant resonances of fast rotating nuclei

    International Nuclear Information System (INIS)

    Jang, S.; Bouyssy, A.

    1987-06-01

    Isoscalar giant resonances in fast rotating nuclei are investigated within the framework of nuclear elasticity by solving the equation of motion of elastic nuclear medium in a rotating frame of reference. Both Coriolis and centrifugal forces are taken into account. The nuclear rotation removes completely the azimuthal degeneracy of the giant resonance energies. Realistic large values of the angular velocity, which are still small as compared to the giant resonance frequencies, are briefly reviewed in relation to allowed high angular momenta. It is shown that for the A=150 region, the Coriolis force is dominating for small values (< ∼ 0.05) of the ratio of angular velocity to resonance frequency, whereas the centrifugal force plays a prominent part in the shift of the split resonance energies for larger values of the ratio. Typical examples of the resonance energies and their fragmentation due to both rotation and deformation are given

  15. Nuclear magnetic resonance imaging of the kidney

    International Nuclear Information System (INIS)

    Hricak, H.; Crooks, L.; Sheldon, P.; Kaufman, L.

    1983-01-01

    The role of nuclear magnetic resonance (NMR) imaging of the kidney was analyzed in 18 persons (6 normal volunteers, 3 patients with pelvocaliectasis, 2 with peripelvic cysts, 1 with renal sinus lipomatosis, 3 with renal failure, 1 with glycogen storage disease, and 2 with polycystic kidney disease). Ultrasound and/or computed tomography (CT) studies were available for comparison in every case. In the normal kidney distinct anatomical structures were clearly differentiated by NMR. The best anatomical detail ws obtained with spin echo (SE) imaging, using a pulse sequence interval of 1,000 msec and an echo delay time of 28 msec. However, in the evaluation of normal and pathological conditions, all four intensity images (SE 500/28, SE 500/56, SE 1,000/28, and SE 1,000/56) have to be analyzed. No definite advantage was found in using SE imaging with a pulse sequence interval of 1,500 msec. Inversion recovery imaging enhanced the differences between the cortex and medulla, but it had a low signal-to-noise level and, therefore, a suboptimal overall resolution. The advantages of NMR compared with CT and ultrasound are discussed, and it is concluded that NMR imaging will prove to be a useful modality in the evaluation of renal disease

  16. Quantitative analysis by nuclear magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wainai, T; Mashimo, K [Nihon Univ., Tokyo. Coll. of Science and Engineering

    1976-04-01

    Recent papers on the practical quantitative analysis by nuclear magnetic resonance spectroscopy (NMR) are reviewed. Specifically, the determination of moisture in liquid N/sub 2/O/sub 4/ as an oxidizing agent for rocket propulsion, the analysis of hydroperoxides, the quantitative analysis using a shift reagent, the analysis of aromatic sulfonates, and the determination of acids and bases are reviewed. Attention is paid to the accuracy. The sweeping velocity and RF level in addition to the other factors must be on the optimal condition to eliminate the errors, particularly when computation is made with a machine. Higher sweeping velocity is preferable in view of S/N ratio, but it may be limited to 30 Hz/s. The relative error in the measurement of area is generally 1%, but when those of dilute concentration and integrated, the error will become smaller by one digit. If impurities are treated carefully, the water content on N/sub 2/O/sub 4/ can be determined with accuracy of about 0.002%. The comparison method between peak heights is as accurate as that between areas, when the uniformity of magnetic field and T/sub 2/ are not questionable. In the case of chemical shift movable due to content, the substance can be determined by the position of the chemical shift. Oil and water contents in rape-seed, peanuts, and sunflower-seed are determined by measuring T/sub 1/ with 90 deg pulses.

  17. Nuclear resonant scattering beamline at SPring-8

    Energy Technology Data Exchange (ETDEWEB)

    Harami, Taikan [Japan Atomic Energy Research Inst., Kamigori, Hyogo (Japan). Kansai Research Establishment

    1996-04-01

    Mainly by Japan Atomic Energy Research Institute, the Institute of Physical and Chemical Research and Japan Synchrotron Radiation Research Institute, the construction of the Super Photon ring-8 GeV (SPring-8) which is the large scale synchrotron radiation facility for a high luminance light source placing emphasis on short wavelength region (shorter than about 1 nm) is in progress at the Harima Science Park City, Hyogo Prefecture. The features of the SPring-8 are the high luminance of light, the good parallelism and directionality of light, the quasi-monochromatic light with variable wavelength, and the possibility of design from straight polarization to circular polarization. The injection system that accelerates electrons up to 8 GeV and the storage ring storing the 8 GeV electrons for long hours, and 61 beamlines are explained. The manufacture of the nuclear resonant scattering beamline as the beamline for joint utilization was begun. Its transport channel and the experiment hutch are shown. By the features of undulator synchrotron radiation, the research on the matters with small recoilless fraction such as biological substances, liquid, gas and others and the research on time-dependent phenomena become feasible anew. The research on the dynamic structural analysis of heme protein is planned. (K.I.)

  18. Nuclear magnetic resonance studies of metabolic regulation

    International Nuclear Information System (INIS)

    Sillerud, L.O.; Han, C.H.; Whaley, T.W.

    1983-01-01

    Nuclear magnetic resonance (NMR) techniques for the detection of the metabolic transformations of biological compounds labeled with stable isotopes, particularly carbon-13 have been explored. We have studied adipose tissue in the intact rat, the exteriorized epididymal fat pad, and the isolated adipocyte. Triacylglycerol metabolism in adipose tissue is regulated by lipogenic factors (insulin, corticosterone, thyroxine, and growth hormone) and lipolytic factors (glucagon and catecholamines). The synthesis of triglyceride from 5.5 mM glucose was stimulated by about 4-fold by 10 nM insulin. Triglyceride synthesis from glucose in the presence of insulin occurred at a rate of 330 nmol/hr/10 6 cells. Since the NMR signals from free and esterified fatty acids and glycerol are distinct, we could directly measure the rate of hormone-stimulated lipolysis. Epinephrine (10 μM) gave a lipolytic rate of 0.30 μmol/hr/10 6 cells as monitored by free-glycerol appearance in the medium. 13 C NMR provides a superior method for the measurement of triglyceride metabolism since it directly measures the changes in the substrates and products in situ

  19. Spatial localization in nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Keevil, Stephen F

    2006-01-01

    The ability to select a discrete region within the body for signal acquisition is a fundamental requirement of in vivo NMR spectroscopy. Ideally, it should be possible to tailor the selected volume to coincide exactly with the lesion or tissue of interest, without loss of signal from within this volume or contamination with extraneous signals. Many techniques have been developed over the past 25 years employing a combination of RF coil properties, static magnetic field gradients and pulse sequence design in an attempt to meet these goals. This review presents a comprehensive survey of these techniques, their various advantages and disadvantages, and implications for clinical applications. Particular emphasis is placed on the reliability of the techniques in terms of signal loss, contamination and the effect of nuclear relaxation and J-coupling. The survey includes techniques based on RF coil and pulse design alone, those using static magnetic field gradients, and magnetic resonance spectroscopic imaging. Although there is an emphasis on techniques currently in widespread use (PRESS, STEAM, ISIS and MRSI), the review also includes earlier techniques, in order to provide historical context, and techniques that are promising for future use in clinical and biomedical applications. (topical review)

  20. Nuclear magnetic resonance studies of lipoproteins

    International Nuclear Information System (INIS)

    Hamilton, J.A.; Morrisett, J.D.

    1986-01-01

    Several nuclei in lipoproteins are magnetically active and are thus potential NMR probes of lipoprotein structure. Table I lists the magnetic isotopes preset in the covalent structures of the molecular constituents of lipoproteins: lipids, proteins, and carbohydrates. Every type of nucleus that is part of the endogenous structure of these molecules has at least one magnetic isotope. Each magnetic nucleus represents an intrinsic and completely nonperturbing probe (when at the natural abundance level) of local molecular motion and magnetic environment. The NMR experiment itself is also nonperturbing and nondestructive. Table I also lists for each nucleus its nuclear spin, its natural isotopic abundance, its sensitivity, and its resonance frequency at two commonly employed magnetic in the low field range (21.14 kG or 2.11 Tesla) and the other in the high field range (47.0 kG or 4.70 Tesla). Of the nuclei listed in Table I, /sup 1/H, /sup 13/C, and /sup 31/P have been the primary ones studied in lipoproteins. The general advantages and disadvantages afforded by these and other nuclei as probes of lipoprotein structure are discussed. /sup 13/C NMR spectroscopy, the method which has had the most extensive application (and probably has the greatest future potential) to lipoproteins, is treated in greatest detail, but many of the principles described apply to other nuclei as well

  1. Quantum information processing and nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Cummins, H.K.

    2001-01-01

    Quantum computers are information processing devices which operate by and exploit the laws of quantum mechanics, potentially allowing them to solve problems which are intractable using classical computers. This dissertation considers the practical issues involved in one of the more successful implementations to date, nuclear magnetic resonance (NMR). Techniques for dealing with systematic errors are presented, and a quantum protocol is implemented. Chapter 1 is a brief introduction to quantum computation. The physical basis of its efficiency and issues involved in its implementation are discussed. NMR quantum information processing is reviewed in more detail in Chapter 2. Chapter 3 considers some of the errors that may be introduced in the process of implementing an algorithm, and high-level ways of reducing the impact of these errors by using composite rotations. Novel general expressions for stabilising composite rotations are presented in Chapter 4 and a new class of composite rotations, tailored composite rotations, presented in Chapter 5. Chapter 6 describes some of the advantages and pitfalls of combining composite rotations. Experimental evaluations of the composite rotations are given in each case. An actual implementation of a quantum information protocol, approximate quantum cloning, is presented in Chapter 7. The dissertation ends with appendices which contain expansions of some equations and detailed calculations of certain composite rotation results, as well as spectrometer pulse sequence programs. (author)

  2. Comparative analysis of nuclear magnetic resonance well logging and nuclear magnetic resonance mud logging

    International Nuclear Information System (INIS)

    Yuan Zugui

    2008-01-01

    The hydrogen atoms in oil and water are able to resonate and generate signals in the magnetic field, which is used by the NMR (nuclear magnetic resonance) technology in petroleum engineering to research and evaluate rock characteristics. NMR well logging was used to measure the physical property parameters of the strata in well bore, whereas NMR mud logging was used to analyze (while drilling) the physical property parameters of cores, cuttings and sidewall coring samples on surface (drilling site). Based on the comparative analysis of the porosity and permeability parameters obtained by NMR well logging and those from analysis of the cores, cuttings and sidewall coring samples by NMR mud logging in the same depth of 13 wells, these two methods are of certain difference, but their integral tendency is relatively good. (authors)

  3. Single-level resonance parameters fit nuclear cross-sections

    Science.gov (United States)

    Drawbaugh, D. W.; Gibson, G.; Miller, M.; Page, S. L.

    1970-01-01

    Least squares analyses of experimental differential cross-section data for the U-235 nucleus have yielded single level Breit-Wigner resonance parameters that fit, simultaneously, three nuclear cross sections of capture, fission, and total.

  4. The Nuclear Magnetic Resonance and its utilization in image formation

    International Nuclear Information System (INIS)

    Bonagamba, T.J.; Tannus, A.; Panepucci, H.

    1987-01-01

    Some aspects about Nuclear Magnetic Resonance (as Larmor Theorem, radio frequency pulse, relaxation of spins system) and its utilization in two dimensional image processing with the necessity of a tomography plane are studied. (C.G.C.) [pt

  5. FY08 Annual Report for Nuclear Resonance Fluorescence Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Warren, Glen A.; Caggiano, Joseph A.

    2009-01-06

    FY08 annual report for project the "Nuclear Resonance Fluorescence Imaging" project. Reviews accomplishments of last 3 years, including U-235 signature search, comparison of different photon sources, and examination of NRF measurements using monochromatic photon source.

  6. Nuclear Magnetic Resonance Study of Nanoscale Ionic Materials

    KAUST Repository

    Oommen, Joanna Mary; Hussain, Muhammad Mustafa; Emwas, Abdul-Hamid M.; Agarwal, Praveen; Archer, Lynden A.

    2010-01-01

    using nuclear magnetic resonance (NMR) spectroscopy. NIMs are relatively stable over a temperature range from 300 to 383 K, rendering them usable in high temperature applications. We confirmed the presence of covalent bonds between the SiO2 core

  7. Proceedings of the nuclear magnetic resonance user meeting

    International Nuclear Information System (INIS)

    1987-01-01

    Studies on utilization of nuclear magnetic resonance, such as: chemical analysis in complexes and organic compounds; structures and magnetic properties of solids; construction of images and; spectrometer designs, are presented. (M.C.K.) [pt

  8. Magnetic resonance vs. computerized tomography, ultrasonic examinations and nuclear medicine

    International Nuclear Information System (INIS)

    Bruna, J.

    1985-01-01

    A symposium on magnetic resonance in nuclear medicine was held from 23rd to 27th January, 1985 in Munich and Garmisch-Partenkirchen. Discussed were suitable methods, the use of contrast media, the evaluation of results, the application of nuclear magnetic resonance in examining various body organs, and the latest apparatus. NMR achievements in medicine were compared to those by other diagnostic methods. (M.D.)

  9. On nuclear reaction duration at the range of overlapping resonances

    International Nuclear Information System (INIS)

    Olkhovsky, V.S.

    1981-01-01

    Nuclear reaction duration above the threshold of overlapping resonances is investigated and its importance to obtain a new information on a collision mechanism is evidenced. It is shown also that the duration of resonant nuclear reactions is asymptotically decreasing according to the law[E 2 n(E)] -1 when the energy E and the number of open channels n(E) are increasing [ru

  10. GEOCHEMICAL CONTROLS ON NUCLEAR MAGNETIC RESONANCE MEASUREMENTS

    International Nuclear Information System (INIS)

    Knight, Rosemary

    2008-01-01

    Proton nuclear magnetic resonance (NMR) is used in the Earth Sciences as a means of obtaining information about the molecular-scale environment of fluids in porous geological materials. Laboratory experiments were conducted to advance our fundamental understanding of the link between the NMR response and the geochemical properties of geological materials. In the first part of this research project, we studied the impact of both the surface-area-to-volume ratio (S/V) of the pore space and the surface relaxivity on the NMR response of fluids in sand-clay mixtures. This study highlighted the way in which these two parameters control our ability to use NMR measurements to detect and quantify fluid saturation in multiphase saturated systems. The second part of the project was designed to explore the way in which the mineralogic form of iron, as opposed to simply the concentration of iron, affects the surface relaxation rate and, more generally, the NMR response of porous materials. We found that the magnitude of the surface relaxation rate was different for the various iron-oxide minerals because of changes in both the surface-area-to-volume ratio of the pore space, and the surface relaxivity. Of particular significance from this study was the finding of an anomalously large surface relaxivity of magnetite compared to that of the other iron minerals. Differences in the NMR response of iron minerals were seen in column experiments during the reaction of ferrihydrite-coated quartz sand with aqueous Fe(II) solutions to form goethite, lepidocrocite and magnetite; indicating the potential use of NMR as a means of monitoring geochemical reactions. The final part of the research project investigated the impact of heterogeneity, at the pore-scale, on the NMR response. This work highlighted the way in which the geochemistry, by controlling the surface relaxivity, has a significant impact on the link between NMR data and the microgeometry of the pore space.

  11. Chiral discrimination in nuclear magnetic resonance spectroscopy

    Science.gov (United States)

    Lazzeretti, Paolo

    2017-11-01

    Chirality is a fundamental property of molecules whose spatial symmetry is characterized by the absence of improper rotations, making them not superimposable to their mirror image. Chiral molecules constitute the elementary building blocks of living species and one enantiomer is favoured in general (e.g. L-aminoacids and D-sugars pervade terrestrial homochiral biochemistry) because most chemical reactions producing natural substances are enantioselective. Since the effect of chiral chemicals and drugs on living beings can be markedly different between enantiomers, the quest for practical spectroscopical methods to scrutinize chirality is an issue of great importance and interest. Nuclear magnetic resonance (NMR) is a topmost analytical technique, but spectrometers currently used are ‘blind’ to chirality, i.e. unable to discriminate the two mirror-image forms of a chiral molecule, because, in the absence of a chiral solvent, the spectral parameters, chemical shifts and spin-spin coupling constants are identical for enantiomers. Therefore, the development of new procedures for routine chiral recognition would offer basic support to scientists. However, in the presence of magnetic fields, a distinction between true and false chirality is mandatory. The former epitomizes natural optical activity, which is rationalized by a time-even pseudoscalar, i.e. the trace of a second-rank tensor, the mixed electric dipole/magnetic dipole polarizability. The Faraday effect, magnetic circular dichroism and magnetic optical activity are instead related to a time-odd axial vector. The present review summarizes recent theoretical and experimental efforts to discriminate enantiomers via NMR spectroscopy, with the focus on the deep connection between chirality and symmetry properties under the combined set of fundamental discrete operations, namely charge conjugation, parity (space inversion) and time (motion) reversal.

  12. Charm and Hidden Charm Scalar Resonances in Nuclear Matter

    NARCIS (Netherlands)

    Tolos, Laura; Molina, Raquel; Gamermann, Daniel; Oset, Eulogio

    2009-01-01

    We study the properties of the scalar charm resonances D(s0)(2317) and D(0)(2400), and the theoretical hidden charm state X(3700) in nuclear matter. We find that for the D(s0)(2317) and X(3700) resonances, with negligible and small width at zero density, respectively, the width becomes about 100 MeV

  13. Proton nuclear magnetic resonance spectroscopy of plasma lipoproteins in malignancy

    International Nuclear Information System (INIS)

    Nabholtz, J.M.; Rossignol, A.; Farnier, M.; Gambert, P.; Tremeaux, J.C.; Friedman, S.; Guerrin, J.

    1988-01-01

    A recent study described a method of detecting malignant tumors by water-supressed proton nuclear magnetic resonance (1 H NMR) study of plasma. We performed a similar study of the W 1/2, a mean of the full width at half height of the resonances of the methyl and methylene groups of the lipids of plasma lipoproteins which is inversely related to the spin-spin apparent relaxation time (T 2 * ). W 1/2 values were measured at a fixed baseline width of 310 Hz. The study was prospective and blinded and comprised 182 subjects consisting of 40 controls, 68 patients with untreated malignancies, 45 with malignant tumors undergoing therapy and 29 benign tumor patients. No differences were seen between any groups that could serve as a basis for a useful clinical test. The major difficulty in the determination of W 1/2 was due to interference of metabolite protons (particularly lactate) within the lipoprotein resonance signal. Triglyceride level was seen to correlate inversely with W 1/2 within malignant patient groups. These discrepant results may be related to differing triglyceride-rich very low density lipoprotein (VLDL) levels in the ;atient populations of each study. We conclude that the water-suppressed 1H NMR of plasma lipoproteins is not a valid measurement for assessing malignancy. (orig.)

  14. Systematic study on nuclear resonant scattering

    International Nuclear Information System (INIS)

    Suarez, A.A.; Freitas, M.L.

    1974-01-01

    New resonant scattering effect of thermal neutron capture gamma rays from Ti and Fe on Sb, Cu, Se and Ce target were observed. These results together with those published by other authors are summarized and discussed in terms of a possible systematic search for new resonant scattering effects

  15. World nuclear performance report 2017

    International Nuclear Information System (INIS)

    Cobb, Jonathan

    2017-01-01

    World Nuclear Association recently published the 2017 edition of the World Nuclear Performance Report. The report presents key metrics that illustrate current performance, both of reactors currently operating and those under construction. The article highlights some of the most important findings of the report. The pace of new build will need to accelerate if nuclear energy is going to make a growing contribution to the global electricity generation mix, a requirement of many projections of future scenarios that aim to meet the objective of limiting the rise average temperatures to below two degrees Celsius, while at the same time meeting the growing worldwide demand for electricity.

  16. World nuclear performance report 2017

    Energy Technology Data Exchange (ETDEWEB)

    Cobb, Jonathan [World Nuclear Association, London (United Kingdom)

    2017-08-15

    World Nuclear Association recently published the 2017 edition of the World Nuclear Performance Report. The report presents key metrics that illustrate current performance, both of reactors currently operating and those under construction. The article highlights some of the most important findings of the report. The pace of new build will need to accelerate if nuclear energy is going to make a growing contribution to the global electricity generation mix, a requirement of many projections of future scenarios that aim to meet the objective of limiting the rise average temperatures to below two degrees Celsius, while at the same time meeting the growing worldwide demand for electricity.

  17. Threedimensional imaging of organ structures by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Waters, W.; Smolorz, J.; Wellner, U.

    1985-01-01

    A simple method for threedimensional imaging of organ structures is presented. The method is based on a special acquisition mode in a nuclear resonance tomograph, exciting layers of 20 cm thickness at different angulations. The display is done by cinematography (which is usually used in nuclear cardiology) projecting the structures in a rotating movement. (orig.) [de

  18. World nuclear performance

    International Nuclear Information System (INIS)

    Muhlheim, M.D.

    1992-01-01

    This update, which appears regularly in each issue of Nuclear Safety, surveys the operations of those power reactors in the world, which have been issued operating licenses. Table I shows the number of such reactors and their net capacities as of June 30, 1992, the end of the three-month period covered in this report Table 2 lists the unit capacity and forced outage rate for each licensed reactor for each of the three-months covered in each report and the cumulative values of these parameters at the end of the covered quarter since the beginning of commercial operation. The Maximum Dependable Capacity (MDC) Unit Capacity (in percent) is defined as follows: (Net electrical energy generated during the reporting period x 100) divided by the product of the number of hours in the reporting period and the MDC of the reactor in question. The forced outage rate (in percent) is defined as: (The total number of hours in the reporting period during which the unit was inoperable as the result of a forced outage x 100) divided by the sum (forced outage hours + operating hours)

  19. Contraband Detection with Nuclear Resonance Fluorescence: Feasibility and Impact

    International Nuclear Information System (INIS)

    Pruet, J; Lange, D

    2007-01-01

    In this report they show that cargo interrogation systems developed to thwart trafficking of illicit nuclear materials could also be powerful tools in the larger fight against contraband smuggling. In particular, in addition to detecting special nuclear materials, cargo scanning systems that exploit nuclear resonance fluorescence to detect specific isotopes can be used to help find: chemical weapons; some drugs as well as some chemicals regulated under the controlled substances act; precious metals; materials regulated under export control laws; and commonly trafficked fluorocarbons

  20. Nuclear investment: performance and opportunity

    International Nuclear Information System (INIS)

    Lacy, B.

    2007-01-01

    Nuclear power plant ownership in the United States has continued its steady trend toward ownership consolidation and removal of assets from rate regulated environments that began in 1998. This is paralleled by changes in companies providing nuclear services and growing talk of building new units. World wide, new nuclear plant construction and related supplier investment is proceeding around the world. The nuclear fuel supply part of the business is seeing interest and excitement that would have been almost inconceivable a decade ago. Nuclear is now increasingly being recognized for its energy, economic and environmental benefits. For investors, this is a time of opportunity. And the opportunity is strongly supported by excellent performance trends and fundamental change sin the US electricity business. But in order to benefit from these changes, investors must remain cautious and be committed to comprehensively and thoroughly understanding the individual and interrelated technical, regulatory and political issues that surround this useful and powerful technology. (orig.)

  1. Resonance internal conversion as a way of accelerating nuclear processes

    International Nuclear Information System (INIS)

    Karpeshin, F.F.

    2006-01-01

    Theory of resonance conversion is presented. Being a natural extension of the traditional internal conversion into the subthreshold area, resonance conversion in a number of cases strongly affects the nuclear processes. Moreover, concentrating the transition strength on the narrow bands corresponding to the spectral atomic lines, it offers a unique tool capable of accelerating nuclear decay rates. Furthermore, along with the conventional nonradiative process of nuclear excitation through NEET and its reverse, TEEN, resonance conversion offers an appropriate mathematics for consideration of a number of cross-invariant processes involving both nuclei and electrons: excitation and deexcitation of the nuclei by hyperfine magnetic field, nuclear spin mixing, hyperfine interaction and magnetic anomalies in the atomic spectra, collisional nuclear excitation via ionization of the shells in the muon decay in the orbit, etc. The mechanisms of the optical pumping of the isomers are also considered, as well as triggering their energy in the resonance field of a laser. The effect is especially high in the hydrogen-like heavy ions due to practical absence of any damping of the resonance. The theory is also generalized to the case of the discrete Auger transitions [ru

  2. High field nuclear magnetic resonance application to polysaccharide chemistry

    International Nuclear Information System (INIS)

    Vincendon, Marc

    1972-01-01

    Nuclear magnetic resonance has been applied to polysaccharide chemistry using time averaging technique and high fields (100 and 250 MHz). The three methyl signals of methyl cellulose and cellulose triacetate are separated, and the C-6 substituent has been identified. Biosynthesis of bacterial cellulose has been performed using deuterium labelled D-glucose and Acetobacter xylinum. Per-acetylated derivative of bacterial cellulose has been studied by NMR; this study permitted us to determine the quantity of deuterium on each position of the anhydro-glucose unit in the polymer. NMR has also been used to see the anomeric end chain of cellulose and amylose derivatives and to show the fixation of bromine and t-butyl group on the free anomeric end chain of cellulose triacetate. (author) [fr

  3. Structural and conformational study of polysaccharides by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Bossennec, Veronique

    1989-01-01

    As some natural polysaccharides are involved in important biological processes, the use of nuclear magnetic resonance appears to be an adapted mean to determine their structure-activity relationship and is therefore the object of this research thesis. By using bi-dimensional proton-based NMR techniques, it is possible to identify minority saccharide units, to determine their conformation, and to identify units which they are bound to. The author reports the application of these methods to swine mucosa heparin, and to heparins displaying a high and low anticoagulant activity. The dermatan sulphate has also been studied, and the NMR analysis allowed some polymer structure irregularities to be identified. A molecular modelling of dermatan sulphate has been performed [fr

  4. Nuclear Magnetic Resonance Study of Nanoscale Ionic Materials

    KAUST Repository

    Oommen, Joanna Mary

    2010-08-13

    Nanoscale ionic materials (NIMs) are a new class of nanomaterials that exhibit interesting properties including negligible vapor pressures and tunable physical states, among others. In this study, we analyzed the temperature-wise performance of NIMs using nuclear magnetic resonance (NMR) spectroscopy. NIMs are relatively stable over a temperature range from 300 to 383 K, rendering them usable in high temperature applications. We confirmed the presence of covalent bonds between the SiO2 core and the sulfonate group and determined relative concentrations of aromatic and aliphatic hydrocarbons. These findings serve as first hand proof-of-concept for the usefulness of NMR analyses in further studies on the diffusive properties of NIMs. © 2010 The Electrochemical Society.

  5. Nuclear magnetic resonance analogs of the Greenberger-Horne-Zeilinger experiment

    International Nuclear Information System (INIS)

    Lloyd, S.

    1998-01-01

    It has been recently shown that analogs of the Greenberger-Horne-Zeilinger experiment, which demonstrates the impossibility of certain types of local hidden variable theories in quantum mechanics, can be performed using nuclear magnetic resonance on spins in molecules at finite temperature. This paper examines the role of decoherence in the microscopic 'measurements' used to perform the NMR experiments. (author)

  6. Neutron resonance analysis for nuclear safeguards and security applications

    Science.gov (United States)

    Paradela, Carlos; Heyse, Jan; Kopecky, Stefan; Schillebeeckx, Peter; Harada, Hideo; Kitatani, Fumito; Koizumi, Mitsuo; Tsuchiya, Harufumi

    2017-09-01

    Neutron-induced reactions can be used to study the properties of nuclear materials of interest in the fields of nuclear safeguards and security. The elemental and isotopic composition of these materials can be determined by using the presence of resonance structures. This idea is the basis of two non-destructive analysis techniques which have been developed at the GELINA neutron time-of-flight facility at JRC-Geel: Neutron Resonance Capture Analysis (NRCA) and Neutron Resonance Transmission Analysis (NRTA). A combination of NRTA and NRCA has been proposed for the characterisation of particle-like debris of melted fuel formed in severe nuclear accidents. In this work, we present a quantitative validation of the NRTA technique which was used to determine the areal densities of Pu enriched reference samples used for safeguards applications. Less than 2% bias has been obtained for the fissile isotopes, with well-known total cross sections.

  7. Evaluation of nuclear magnetic resonance spectroscopy variability

    Energy Technology Data Exchange (ETDEWEB)

    Barreto, Felipe Rodrigues; Salmon, Carlos Ernesto Garrido, E-mail: garrido@ffclrp.usp.br [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Fac. de Filisofia, Ciencias e Letras; Otaduy, Maria Concepcion Garcia [Universidade de Sao Paulo (FAMUS/USP), Sao Paulo, SP (Brazil). Fac. de Medicina. Departamento de Radiologia

    2014-11-01

    Introduction: the intrinsically high sensitivity of Magnetic Resonance Spectroscopy (MRS) causes considerable variability in metabolite quantification. In this study, we evaluated the variability of MRS in two research centers using the same model of magnetic resonance image scanner. Methods: two metabolic phantoms were created to simulate magnetic resonance spectra from in vivo hippocampus. The phantoms were filled with the same basic solution containing the following metabolites: N-acetyl-aspartate, creatine, choline, glutamate, glutamine and inositol. Spectra were acquired over 15 months on 26 acquisition dates, resulting in a total of 130 spectra per center. Results: the phantoms did not undergo any physical changes during the 15-month period. Temporal analysis from both centers showed mean metabolic variations of 3.7% in acquisitions on the same day and of 8.7% over the 15-month period. Conclusion: The low deviations demonstrated here, combined with the high specificity of Magnetic Resonance Spectroscopy, confirm that it is feasible to use this technique in multicenter studies in neuroscience research. (author)

  8. Baryons and baryon resonances in nuclear matter

    Science.gov (United States)

    Lenske, Horst; Dhar, Madhumita; Gaitanos, Theodoros; Cao, Xu

    2018-01-01

    Theoretical approaches to the production of hyperons and baryon resonances in elementary hadronic reactions and heavy ion collisions are reviewed. The focus is on the production and interactions of baryons in the lowest SU(3) flavor octet and states from the next higher SU(3) flavor decuplet. Approaches using the SU(3) formalism for interactions of mesons and baryons and effective field theory for hyperons are discussed. An overview of application to free space and in-medium baryon-baryon interactions is given and the relation to a density functional theory is indicated. The intimate connection between baryon resonances and strangeness production is shown first for reactions on the nucleon. Pion-induced hypernuclear reactions are shown to proceed essentially through the excitation of intermediate nucleon resonances. Transport theory in conjunction with a statistical fragmentation model is an appropriate description of hypernuclear production in antiproton and heavy ion induced fragmentation reactions. The excitation of subnuclear degrees of freedom in peripheral heavy ion collisions at relativistic energies is reviewed. The status of in-medium resonance physics is discussed.

  9. Parent di-nuclear quasimolecular states as exotic resonant states

    International Nuclear Information System (INIS)

    Grama, N.

    2002-01-01

    It in shown that the parent di-nuclear quasimolecular state is an exotic resonant state that corresponds to a S-matrix pole in the neighbourhood of an attractor in the k-plane. The properties of the parent quasimolecular states i.e. energy, widths, deviation from the linear dependence of the energy on l(l + 1) doorway character and criteria for observability, result naturally from the general properties of the exotic resonant states. (author)

  10. NMR magnetic field controller for pulsed nuclear magnetic resonance experiments

    International Nuclear Information System (INIS)

    Scheler, G.; Anacker, M.

    1975-01-01

    A nuclear magnetic resonance controller for magnetic fields, which can also be used for pulsed NMR investigations, is described. A longtime stability of 10 -7 is achieved. The control signal is generated by a modified time sharing circuit with resonance at the first side band of the 2 H signal. An exact calibration of the magnetic field is achieved by the variation of the H 1 - or of the time-sharing frequency. (author)

  11. Apparatus and method for nuclear magnetic resonance scanning and mapping

    International Nuclear Information System (INIS)

    Damadian, R.V.

    1983-01-01

    An improved apparatus and method is disclosed for analyzing the chemical and structural composition of a specimen including whole-body specimens which may include, for example, living mammals, utilizing nuclear magnetic resonance (NMR) techniques. A magnetic field space necessary to obtain an NMR signal characteristic of the chemical structure of the specimen is focused to provide a resonance domain of selectable size, which may then be moved in a pattern with respect to the specimen to scan the specimen

  12. Nuclear magnetic resonance spectroscopy in food applications: a critical appraisal

    International Nuclear Information System (INIS)

    Divakar, S.

    1998-01-01

    Usefulness of Nuclear Magnetic Resonance (NMR) spectroscopy in food applications is presented in this review. Some of the basic concepts of NMR pertaining to one-dimensional and two-dimensional techniques, solid-state NMR and Magnetic Resonance Imaging (MRI) are discussed. Food applications dealt with encompass such diverse areas like nature and state of water in foods, detection and quantitation of important constituents of foods, intact food systems and NMR related to food biology. (author)

  13. Electron and nuclear magnetic resonances in compounds and metallic hydrides

    International Nuclear Information System (INIS)

    Brasil Filho, N.

    1985-11-01

    Proton pulsed Nuclear Magnetic Resonance measurements were performed on the metallic hydrides ZrCr 2 H x (x = 2, 3, 4) and ZrV 2 H y (y = 2, 3, 4, 5) as a function of temperature between 180 and 400K. The ultimate aim was the investigation of the relaxation mechanisms in these systems by means of the measurement of both the proton ( 1 H) spin-lattice (T 1 ) and spin-spin (T 2 ) relaxation times and to use these data to obtain information about the diffusive motion of the hydrogen atoms. The diffusional activation energies, the jump frequencies and the Korringa constant, C k , related with the conduction electron contribution to the 1 H relaxation were determined for the above hydrides as a function of hydrogen concentration. Our results were analysed in terms of the relaxation models described by Bloembergen, Purcell and Pound (BPP model) and by Torrey. The Korringa type relaxation due to the conduction electrons in metallic systems was also used to interpret the experimental results. We also present the Electron Paramagnetic Ressonance (EPR) study of Gd 3+ , Nd 3+ and Er 3+ ions as impurities in several AB 3 intermetallic compounds where A = LA, Ce, Y, Sc, Th, Zr and B = Rh, Ir, Pt. The results were analysed in terms of the multiband model previously suggested to explain the behaviour of the resonance parameter in AB 2 Laves Phase compounds. (author) [pt

  14. Computer Assisted Instruction (Cain) For Nuclear Magnetic Resonance Spectroscopy

    International Nuclear Information System (INIS)

    Jaturonrusmee, Wasna; Arthonvorakul, Areerat; Assateranuwat, Adisorn

    2005-10-01

    A computer assisted instruction program for nuclear magnetic resonance spectroscopy was developed by using Author ware 5.0, Adobe Image Styler 1.0, Adobe Photo shop 7.0 and Flash MX. The contents included the basic theory of 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, the instrumentation of NMR spectroscopy, the two dimensional (2D) NMR spectroscopy and the interpretation of NMR spectra. The program was also provided examples, and exercises, with emphasis on NMR spectra interpretation to determine the structure of unknown compounds and solutions for self study. The questionnaire from students showed that they were very satisfied with the software

  15. Basic principles of nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Valk, J.; MacLean, C.; Algra, P.R.

    1985-01-01

    The intent of this book is to help clinicians understand the basic physical principles of magnetic resonance (MR) imaging. The book consists of the following: a discussion of elementary considerations; pulse sequencing; localization of MR signals in space; MR equipment; MR contrast agents; clinical applications; MR spectroscopy; and biological effects of MR imaging; a set of appendixes; and a bibliography. Illustrations and images are included

  16. Worldwide nuclear-plant performance

    International Nuclear Information System (INIS)

    Surrey, J.; Thomas, S.

    1980-01-01

    The authors compare the performance of different reactor systems to identify the determinants of plant performance, to examine the evidence of technological maturation, and to discover the principal causes of outage or unavailability. In the light of the findings, they discuss the implications for the UK regarding reactor choice and technology development. They make no judgements about the relative merits of nuclear and fossil-fuel plants, or about safety. (author)

  17. Nuclear Resonance Fluorescence and Isotopic Mapping of Containers

    Science.gov (United States)

    Johnson, Micah S.; McNabb, Dennis P.

    2009-03-01

    National security programs have expressed interest in developing systems to isotopically map shipping containers, fuel assemblies, and waste barrels for various materials including special nuclear material (SNM). Current radiographic systems offer little more than an ambiguous density silhouette of a container's contents. In this paper we will present a system being developed at LLNL to isotopically map containers using the nuclear resonance fluorescence (NRF) method. Recent experimental measurements on NRF strengths in SNM are discussed.

  18. Effect of resonance line shape on precision measurements of nuclear magnetic resonance shifts

    International Nuclear Information System (INIS)

    Kachurin, A.M.; Smelyanskij, A.Ya.

    1986-01-01

    Effect of resonance line shape on the systematic error of precision measurements of nuclear magnetic resonance (NMR) shifts of high resolution (on the center of NMR dispersion line) is analysed. Effect of the device resonance line form-function asymmetry is evaluated; the form-function is determined by configuration of the spectrometer magnetic field and enters the convolution, which describes the resonance line form. It is shown that with the increase of the relaxation line width the form-function effect on the measurement error yields to zero. The form-function effect on measurements and correction of a phase angle of NMR detection is evaluated. The method of semiquantitative evaluation of resonance line and NMR spectrometer parameters, guaranteeing the systematic error of the given infinitesimal, is presented

  19. Susceptibility effects in nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Ziener, Christian Herbert

    2008-01-01

    The properties of dephasing and the resulting relaxation of the magnetization are the basic principle on which all magnetic resonance imaging methods are based. The signal obtained from the gyrating spins is essentially determined by the properties of the considered tissue. Especially the susceptibility differences caused by magnetized materials (for example, deoxygenated blood, BOLD-effect) or magnetic nanoparticles are becoming more important for biomedical imaging. In the present work, the influence of such field inhomogeneities on the NMR-signal is analyzed. (orig.)

  20. Nuclear resonance apparatus including means for rotating a magnetic field

    International Nuclear Information System (INIS)

    Sugimoto, H.

    1983-01-01

    A nuclear magnetic resonance apparatus including magnet apparatus for generating a homogeneous static magnetic field between its magnetic poles, shims of a magnetic substance mounted on the magnetic poles to apply a first gradient magnetic field intensity distribution in a direction orthogonal as to the direction of line of magnetic force of the static magnetic field, gradient magnetic field generating electromagnetic apparatus for generating a second gradient magnetic field having a gradient magnetic field intensity distribution in superimposition with the static magnetic field and for changing the magnetic field gradient of the first gradient magnetic field, an oscillator for generating an oscillating output having a frequency corresponding to the nuclear magnetic resonance condition of an atomic nucleus to be measured, a coil wound around a body to be examined for applying the output of said oscillator as electromagnetic waves upon the body, a receiver for detecting the nuclear magnetic resonance signals received by the coil, a gradient magnetic field controller making a magnetic field line equivalent to the combined gradient magnetic fields and for rotating the line along the section of the body to be examined by controlling said gradient magnetic field generating electromagnetic apparatus and devices for recording the nuclear magnetic resonance signals, for reconstructing the concentration distribution of the specific atomic nuclei in the section of the body, and a display unit for depicting the result of reconstruction

  1. Nuclear magnetic resonance of D(-)-α-amino-benzyl penicillin

    International Nuclear Information System (INIS)

    Aguiar, Monica R.M.P.; Gemal, Andre L.; San Gil, Rosane A.S.; Menezes, Sonia M.C.

    1995-01-01

    The development of new drugs from penicillins has induced the study of this substances by nuclear magnetic resonance. Several samples of D(-)-α-amino-benzyl penicillin were analysed using 13 C NMR techniques in aqueous solution and solid state. Spectral data of this compounds were shown and the results were presented and analysed

  2. Selection of planes in nuclear magnetic resonance tomography

    International Nuclear Information System (INIS)

    Bonagamba, T.J.

    1986-01-01

    A prototype aiming to obtain images in nuclear magnetic resonance tomography was developed, by adjusting NMR spectrometer in the IFQSC Laboratory. The techniques for selecting planes were analysed by a set of computer codes, which were elaborated from Bloch equation solutions to simulate the spin system behaviour. Images were obtained using planes with thickness inferior to 1 cm. (M.C.K.)

  3. Communication patterns in the field of nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Tomov, D.; Filipov, F.; Kolev, N.

    1986-01-01

    A scientometric analysis of publications presented in four secondary information sources on the problem of nuclear magnetic resonance in physics, biomedicine and technology was carried out. A dynamic growth of the number of articles in biomedicine over 1982 to 1984 was established. Secondary publications play an important role in scientific communications as revealed by citation analysis. (author)

  4. Nuclear magnetic resonance in cardiology: cardiac MRI

    International Nuclear Information System (INIS)

    Fernandez, Claudio C.

    2003-01-01

    As a new gold standard for mass, volume and flow, the magnetic resonance imaging (MRI) is probably the most rapidly evolving technique in the cardiovascular diagnosis. An integrated cardiac MRI examination allows the evaluation of morphology, global and regional function, coronary anatomy, perfusion, viability and myocardial metabolism, all of them in only one diagnostic test and in a totally noninvasive manner. The surgeons can obtain relevant information on all aspects of diseases of the heart and great vessels, which include anatomical details and relationships with the greatest field of view, and may help to reduce the number of invasive procedures required in pre and postoperative evaluation. However, despite these excellent advantages the present clinical utilization of MRI is still too often restricted to few pathologies or case studies in which other techniques fail to identify the cardiac or cardiovascular abnormalities. If magnetic resonance is an excellent method for diagnosing so many different cardiac conditions, why is so little it used in routine cardiac practice? Cardiologists are still not very familiar with the huge possibilities or cardiovascular MRI utilities. Our intention is to give a comprehensive survey of many of the clinical applications of this challenger technique in the study of the heart and great vessels. Those who continue to ignore this important and mature imaging technique will rightly fail to benefit. (author) [es

  5. New Approaches to Quantum Computing using Nuclear Magnetic Resonance Spectroscopy

    International Nuclear Information System (INIS)

    Colvin, M; Krishnan, V V

    2003-01-01

    The power of a quantum computer (QC) relies on the fundamental concept of the superposition in quantum mechanics and thus allowing an inherent large-scale parallelization of computation. In a QC, binary information embodied in a quantum system, such as spin degrees of freedom of a spin-1/2 particle forms the qubits (quantum mechanical bits), over which appropriate logical gates perform the computation. In classical computers, the basic unit of information is the bit, which can take a value of either 0 or 1. Bits are connected together by logic gates to form logic circuits to implement complex logical operations. The expansion of modern computers has been driven by the developments of faster, smaller and cheaper logic gates. As the size of the logic gates become smaller toward the level of atomic dimensions, the performance of such a system is no longer considered classical but is rather governed by quantum mechanics. Quantum computers offer the potentially superior prospect of solving computational problems that are intractable to classical computers such as efficient database searches and cryptography. A variety of algorithms have been developed recently, most notably Shor's algorithm for factorizing long numbers into prime factors in polynomial time and Grover's quantum search algorithm. The algorithms that were of only theoretical interest as recently, until several methods were proposed to build an experimental QC. These methods include, trapped ions, cavity-QED, coupled quantum dots, Josephson junctions, spin resonance transistors, linear optics and nuclear magnetic resonance. Nuclear magnetic resonance (NMR) is uniquely capable of constructing small QCs and several algorithms have been implemented successfully. NMR-QC differs from other implementations in one important way that it is not a single QC, but a statistical ensemble of them. Thus, quantum computing based on NMR is considered as ensemble quantum computing. In NMR quantum computing, the spins with

  6. Sealed magic angle spinning nuclear magnetic resonance probe and process for spectroscopy of hazardous samples

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Herman M.; Washton, Nancy M.; Mueller, Karl T.; Sears, Jr., Jesse A.; Townsend, Mark R.; Ewing, James R.

    2016-06-14

    A magic-angle-spinning (MAS) nuclear magnetic resonance (NMR) probe is described that includes double containment enclosures configured to seal and contain hazardous samples for analysis. The probe is of a modular design that ensures containment of hazardous samples during sample analysis while preserving spin speeds for superior NMR performance and convenience of operation.

  7. Analysis of sesquiterpene lactones, lignans, and flavonoids in wormwood (Artemisia absinthium L.) using high-performance liquid chromatography (HPLC)-mass spectrometry, reversed phase HPLC, and HPLC-solid phase extraction-nuclear magnetic resonance.

    Science.gov (United States)

    Aberham, Anita; Cicek, Serhat Sezai; Schneider, Peter; Stuppner, Hermann

    2010-10-27

    Today, the medicinal use of wormwood (Artemisia absinthium) is enjoying a resurgence of popularity. This study presents a specific and validated high-performance liquid chromatography (HPLC)-diode array detection method for the simultaneous determination and quantification of bioactive compounds in wormwood and commercial preparations thereof. Five sesquiterpene lactones, two lignans, and a polymethoxylated flavonoid were baseline separated on RP-18 material, using a solvent gradient consisting of 0.085% (v/v) o-phosphoric acid and acetonitrile. The flow rate was 1.0 mL/min, and chromatograms were recorded at 205 nm. The stability of absinthin was tested exposing samples to light, moisture, and different temperatures. Methanolic and aqueous solutions of absinthin were found to be stable for up to 6 months. This was also the case when the solid compound was kept in the refrigerator at -35 °C. In contrast, the colorless needles, when stored at room temperature, turned yellow. Three degradation compounds (anabsin, anabsinthin, and the new dimer 3'-hydroxyanabsinthin) were identified by HPLC-mass spectrometry and HPLC-solid-phase extraction-nuclear magnetic resonance and quantified by the established HPLC method.

  8. Electron-nuclear magnetic resonance in the inverted state

    International Nuclear Information System (INIS)

    Ignatchenko, V.A.; Tsifrinovich, V.I.

    1975-01-01

    The paper considers the susceptibility of the electron-nucleus system of a ferromagnet when nuclear magnetization is inverted with respect to the hyperfine field direction. The inverted state is a situation in which nuclear magnetization is turned through π relative to its equilibrium orientation, whereas electron magnetization is in an equilibrium state with respect to an external magnetic field. The consideration is carried out for a thin plate magnetized in its plane. Amplification of a weak radiofrequency signal can be attained under the fulfilment of an additional inequality relating the interaction frequency with electron and nuclear relaxation parameters. The gain may exceed the gain for an inverted nuclear system in magnetically disordered substances. In the range of strong interaction between the frequencies of ferromagnetic (FMR) and nuclear magnetic (NMR) resonances the electron-nuclear magnetic resonance (ENMR) spectrum possesses a fine structure which is inverse to that obtained for the ENMR spectrum in a normal state. The inverted state ENMR line shape is analysed in detail for the case of so weak HF fields that the relaxation conditions may be regarded as stationary. The initial (linear) stages of a forced transient process arising in an electron-nuclear system under the effect of a strong HF field are briefly analysed

  9. Ultrasonic-resonator-combined apparatus for purifying nuclear aerosol particles

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Suxia; Zhang, Quanhu; Li, Sufen; Chen, Chen; Su, Xianghua [Xi' an Hi-Tech Institute, Xi' an (China)

    2017-12-15

    The radiation hazards of radionuclides in the air arising from the storage room of nuclear devices to the operators cannot be ignored. A new ultrasonic-resonator-combined method for purifying nuclear aerosol particles is introduced. To remove particles with diameters smaller than 0.3 μm, an ultrasonic chamber is induced to agglomerate these submicron particles. An apparatus which is used to purify the nuclear aerosol particles is described in the article. The apparatus consists of four main parts: two filtering systems, an ultrasonic chamber and a high-pressure electrostatic precipitator system. Finally, experimental results demonstrated the effectiveness of the implementation of the ultrasonic resonators. The feasibility of the method is proven by its application to the data analysis of the experiments.

  10. Analysis and characterization. Nuclear resonant scattering with the synchrotron radiation

    International Nuclear Information System (INIS)

    Ruffer, R.; Teillet, J.

    2003-01-01

    The nuclear resonant scattering using the synchrotron radiation combines the uncommon properties of the Moessbauer spectroscopy and those of the synchrotron radiation. Since its first observation in 1984, this technique and its applications have been developed rapidly. The nuclear resonant scattering is now a standard technique for all the synchrotron radiation sources of the third generation. As the Moessbauer spectroscopy, it is a method of analysis at the atomic scale and a non destructive method. It presents the advantage not to require the use of radioactive sources of incident photons which can be difficult to make, of a lifetime which can be short and of an obviously limited intensity. The current applications are the hyperfine spectroscopy and the structural dynamics. In hyperfine spectroscopy, the nuclear resonant scattering can measure the same size than the Moessbauer spectroscopy. Nevertheless, it is superior in the ranges which exploit the specific properties of the synchrotron radiation, such as the very small samples, the monocrystals, the measures under high pressures, the geometry of small angle incidence for surfaces and multilayers. The structural dynamics, in a time scale of the nanosecond to the microsecond can be measured in the temporal scale. Moreover, the nuclear inelastic scattering gives for the first time a tool which allows to have directly the density of states of phonons and then allow to deduce the dynamical and thermodynamical properties of the lattice. The nuclear resonant scattering technique presented here, which corresponds to the Moessbauer spectroscopy technique (SM), is called 'nuclear forward scattering' (NFS). Current applications in physics and chemistry are develop. The NFS is compared to the usual SM technique in order to reveal its advantages and disadvantages. (O.M.)

  11. Anti-inflammatory effects, nuclear magnetic resonance identification, and high-performance liquid chromatography isolation of the total flavonoids from Artemisia frigida

    Directory of Open Access Journals (Sweden)

    Qinghu Wang

    2016-04-01

    Full Text Available The aerial parts of Artemisia frigida Willd. are used to treat joint swelling, renal heat, abnormal menstruation, and sore carbuncle. The anti-inflammatory effects of A. frigida have been well-known in folk medicine, suggesting that components extracted from A. frigida could potentially treat inflammatory disease. With the aim of discovering bioactive compounds, in this study, we extracted total flavonoids from the aerial parts of A. frigida and investigated their anti-inflammatory effects against inflammation induced by carrageenan and egg albumin in rats. At the doses studied, total flavonoids (100 mg/kg, 200 mg/kg, and 400 mg/kg and some isolated compounds (30 mg/kg showed significant and dose-dependent anti-inflammatory effects. According to the high-performance liquid chromatography analysis of the total flavonoids from A. frigida, there are five major compounds, namely, 5-hydroxy-3′,4′-dimethoxy-7-O-β-d-glucuronide (F1, 5-hydroxy-3′,4′,5′-trimethoxy-7-O-β-d-glucuronide (F2, 5,7,3′-trihydroxy-6,4′-dimethoxyflavone (F3, 5,3′-dihydroxy-6,7,4′-trimethoxyflavone (F4, and 5,3′-dihydroxy-3,6,7,4′-tetramethoxyflavone (F5, which may explain the anti-inflammatory activity.

  12. Updated methodology for nuclear magnetic resonance characterization of shales

    Science.gov (United States)

    Washburn, Kathryn E.; Birdwell, Justin E.

    2013-08-01

    Unconventional petroleum resources, particularly in shales, are expected to play an increasingly important role in the world's energy portfolio in the coming years. Nuclear magnetic resonance (NMR), particularly at low-field, provides important information in the evaluation of shale resources. Most of the low-field NMR analyses performed on shale samples rely heavily on standard T1 and T2 measurements. We present a new approach using solid echoes in the measurement of T1 and T1-T2 correlations that addresses some of the challenges encountered when making NMR measurements on shale samples compared to conventional reservoir rocks. Combining these techniques with standard T1 and T2 measurements provides a more complete assessment of the hydrogen-bearing constituents (e.g., bitumen, kerogen, clay-bound water) in shale samples. These methods are applied to immature and pyrolyzed oil shale samples to examine the solid and highly viscous organic phases present during the petroleum generation process. The solid echo measurements produce additional signal in the oil shale samples compared to the standard methodologies, indicating the presence of components undergoing homonuclear dipolar coupling. The results presented here include the first low-field NMR measurements performed on kerogen as well as detailed NMR analysis of highly viscous thermally generated bitumen present in pyrolyzed oil shale.

  13. Magnetic resonance imaging and nuclear magnetic resonance investigations of bentonite systems

    Energy Technology Data Exchange (ETDEWEB)

    Dvinskikh, Sergey V.; Furo, Istvan (Industrial NMR Centre and Div. of Physical Chemistry, Dept. of Chemistry, Royal Institute of Technology, Stockholm (Sweden))

    2009-09-15

    This report summarizes results from a set of magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) experiments performed on Ca and Na montmorillonite samples interacting with water. The primary goal with these studies was to provide, in a non-invasive manner, a quantitative measure of bentonite distribution in extended samples during and after different physical processes such as swelling and sedimentation and on the time scale from minutes to years. Additionally, we also studied the distribution of foreign particles (such as native minerals as well as magnetic model particles) within bentonite systems and performed some diffusion NMR experiments with the aim of characterizing the state of colloids that form after clay dissolution. Both natural montmorillonites and purified and ion-exchanged montmorillonite clays were investigated. The primary variables were clay composition and water ionic strength. Bulk samples confined in a vertical tube and in a horizontal channel were investigated. A critical issue for the stability of clay buffer layer in deep underground repository is to prevent or minimize the release of clay particles into the water phase. In our experiments, the most significant particle losses were found for Na-MX80 clay exposed to water with low ionic strength. With increasing the concentration of CaCl{sub 2} in the water phase both swelling and particle release are slowed down but not completely eliminated due probably to gradual change of water ion content via ion exchange with the clay itself. For natural MX80 samples, in spite of significant swelling expansion, no clay particle release above the sensitivity limit of 0.001 volume% was observed. Ca-MX80 exhibited the smallest expansion and no trace of clay particle released into the aqueous phase

  14. Magnetic resonance imaging and nuclear magnetic resonance investigations of bentonite systems

    International Nuclear Information System (INIS)

    Dvinskikh, Sergey V.; Furo, Istvan

    2009-09-01

    This report summarizes results from a set of magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) experiments performed on Ca and Na montmorillonite samples interacting with water. The primary goal with these studies was to provide, in a non-invasive manner, a quantitative measure of bentonite distribution in extended samples during and after different physical processes such as swelling and sedimentation and on the time scale from minutes to years. Additionally, we also studied the distribution of foreign particles (such as native minerals as well as magnetic model particles) within bentonite systems and performed some diffusion NMR experiments with the aim of characterizing the state of colloids that form after clay dissolution. Both natural montmorillonites and purified and ion-exchanged montmorillonite clays were investigated. The primary variables were clay composition and water ionic strength. Bulk samples confined in a vertical tube and in a horizontal channel were investigated. A critical issue for the stability of clay buffer layer in deep underground repository is to prevent or minimize the release of clay particles into the water phase. In our experiments, the most significant particle losses were found for Na-MX80 clay exposed to water with low ionic strength. With increasing the concentration of CaCl 2 in the water phase both swelling and particle release are slowed down but not completely eliminated due probably to gradual change of water ion content via ion exchange with the clay itself. For natural MX80 samples, in spite of significant swelling expansion, no clay particle release above the sensitivity limit of 0.001 volume% was observed. Ca-MX80 exhibited the smallest expansion and no trace of clay particle released into the aqueous phase

  15. Chemical variability along the value chains of turmeric (Curcuma longa): a comparison of nuclear magnetic resonance spectroscopy and high performance thin layer chromatography.

    Science.gov (United States)

    Booker, Anthony; Frommenwiler, Debora; Johnston, Deborah; Umealajekwu, Chinenye; Reich, Eike; Heinrich, Michael

    2014-03-14

    Herbal medicine value chains have generally been overlooked compared with food commodities. Not surprisingly, revenue generation tends to be weighted towards the end of the chain and consequently the farmers and producers are the lowest paid beneficiaries. Value chains have an impact both on the livelihood of producers and on the composition and quality of products commonly sold locally and globally and consequently on the consumers. In order to understand the impact of value chains on the composition of products, we studied the production conditions for turmeric (Curcuma longa) and the metabolomic composition of products derived from it. We aimed at integrating these two components in order to gain a better understanding of the effect of different value chains on the livelihoods of some producers. This interdisciplinary project uses a mixed methods approach. Case studies were undertaken on two separate sites in India. Data was initially gathered on herbal medicine value chains by means of semi-structured interviews and non-participant observations. Samples were collected from locations in India, Europe and the USA and analysed using (1)H NMR spectroscopy coupled with multivariate analysis software and with high performance thin layer chromatography (HPTLC). We investigate medicinal plant value chains and interpret the impact different value chains have on some aspects of the livelihoods of producers in India and, for the first time, analytically assess the chemical variability and quality implications that different value chains may have on the products available to end users in Europe. There are benefits to farmers that belonged to an integrated chain and the resulting products were subject to a higher standard of processing and storage. By using analytical methods, including HPTLC and (1)H NMR spectroscopy, it has been possible to correlate some variations in product composition for selected producers and identify strengths and weaknesses of some types of value

  16. Resonant nuclear battery may aid in mitigating the greenhouse effect

    International Nuclear Information System (INIS)

    Brown, P.M.

    1989-01-01

    A new process for the direct conversion of radioactive decay energy directly into electricity of a usable form is currently being developed by Peripheral Systems, Inc. of Portland, Oregon. United States Patent 4,835,433 was issued May 30, 1989 to protect this Resonant Nuclear Power Supply. When developed, this system promises cheap, reliable power from a package small and light enough to be mobile and an energy density great enough for use as a space-based power supply. One of the potential domestic applications could be to power electric automobiles. Use in highly populated areas would have a tremendous beneficial effect on the ecology. The principle of operation for the resonant nuclear power supply is an LCR (inductance capacitance resistance) resonant tank circuit oscillating at its self-resonant frequency (at resonance, the inductive reactance and the capacitive reactance cancel to leave the ohmic resistance of the circuit as the only major loss of energy). A means for absorbing the natural radioactive decay energy emitted from an alpha or beta source is provided in the primary tank circuit and contributes an amount of energy, by means of the beta voltaic effect, in excess of the energy required to sustain the oscillation of the LCR primary tank. A transformer is impedance matched to this oscillating primary circuit for efficient energy transfer of the excess energy to a secondary output circuit, which yields net electrical power in a high-frequency usable form to drive a load

  17. Polarization of nuclear spins by a cold nanoscale resonator

    International Nuclear Information System (INIS)

    Butler, Mark C.; Weitekamp, Daniel P.

    2011-01-01

    A cold nanoscale resonator coupled to a system of nuclear spins can induce spin relaxation. In the low-temperature limit where spin-lattice interactions are ''frozen out,'' spontaneous emission by nuclear spins into a resonant mechanical mode can become the dominant mechanism for cooling the spins to thermal equilibrium with their environment. We provide a theoretical framework for the study of resonator-induced cooling of nuclear spins in this low-temperature regime. Relaxation equations are derived from first principles, in the limit where energy donated by the spins to the resonator is quickly dissipated into the cold bath that damps it. A physical interpretation of the processes contributing to spin polarization is given. For a system of spins that have identical couplings to the resonator, the interaction Hamiltonian conserves spin angular momentum, and the resonator cannot relax the spins to thermal equilibrium unless this symmetry is broken by the spin Hamiltonian. The mechanism by which such a spin system becomes ''trapped'' away from thermal equilibrium can be visualized using a semiclassical model, which shows how an indirect spin-spin interaction arises from the coupling of multiple spins to one resonator. The internal spin Hamiltonian can affect the polarization process in two ways: (1) By modifying the structure of the spin-spin correlations in the energy eigenstates, and (2) by splitting the degeneracy within a manifold of energy eigenstates, so that zero-frequency off-diagonal terms in the density matrix are converted to oscillating coherences. Shifting the frequencies of these coherences sufficiently far from zero suppresses the development of resonator-induced correlations within the manifold during polarization from a totally disordered state. Modification of the spin-spin correlations by means of either mechanism affects the strength of the fluctuating spin dipole that drives the resonator. In the case where product states can be chosen as energy

  18. Missing and Spurious Level Corrections for Nuclear Resonances

    International Nuclear Information System (INIS)

    Mitchell, G E; Agvaanluvsan, U; Pato, M P; Shriner, J F

    2005-01-01

    Neutron and proton resonances provide detailed level density information. However, due to experimental limitations, some levels are missed and some are assigned incorrect quantum numbers. The standard method to correct for missing levels uses the experimental widths and the Porter-Thomas distribution. Analysis of the spacing distribution provides an independent determination of the fraction of missing levels. We have derived a general expression for such an imperfect spacing distribution using the maximum entropy principle and applied it to a variety of nuclear resonance data. The problem of spurious levels has not been extensively addressed

  19. Hybrid model for the decay of nuclear giant resonances

    International Nuclear Information System (INIS)

    Hussein, M.S.

    1986-12-01

    The decay properties of nuclear giant multipole resonances are discussed within a hybrid model that incorporates, in a unitary consistent way, both the coherent and statistical features. It is suggested that the 'direct' decay of the GR is described with continuum first RPA and the statistical decay calculated with a modified Hauser-Feshbach model. Application is made to the decay of the giant monopole resonance in 208 Pb. Suggestions are made concerning the calculation of the mixing parameter using the statistical properties of the shell model eigenstates at high excitation energies. (Author) [pt

  20. Real stabilization method for nuclear single-particle resonances

    International Nuclear Information System (INIS)

    Zhang Li; Zhou Shangui; Meng Jie; Zhao Enguang

    2008-01-01

    We develop the real stabilization method within the framework of the relativistic mean-field (RMF) model. With the self-consistent nuclear potentials from the RMF model, the real stabilization method is used to study single-particle resonant states in spherical nuclei. As examples, the energies, widths, and wave functions of low-lying neutron resonant states in 120 Sn are obtained. These results are compared with those from the scattering phase-shift method and the analytic continuation in the coupling constant approach and satisfactory agreements are found

  1. Charge-exchange giant resonances as probes of nuclear structure

    International Nuclear Information System (INIS)

    Blomgren, J.

    2001-09-01

    Giant resonances populated in charge-exchange reactions can reveal detailed information about nuclear structure properties, in spite of their apparent featurelessness. The (p,n) and (n,p) reactions - as well as their analog reactions - proceed via the same nuclear matrix element as beta decay. Thereby, they are useful for probing electroweak properties in nuclei, especially for those not accessible to beta decay. The nuclear physics aspects of double beta decay might be investigated in double charge-exchange reactions. detailed nuclear structure information, such as the presence of ground-state correlations, can be revealed via identification of 'first-forbidden' transitions. In addition, astrophysics aspects and halo properties of nuclei have been investigated in charge exchange. Finally, these experiments have questioned our knowledge of the absolute strength of the strong interaction

  2. Visualization of cerebellopontine angle lesions by nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Ochiai, Chikayuki; Takakura, Kintomo; Machida, Tohru; Araki, Tsutomu; Iio, Masahiro; Basugi, Norihiko.

    1983-01-01

    The preliminary results from the clinical use a prototype whole body nuclear magnetic resonance (NMR) machine constructed by Toshiba Inc. are presented. Cranial NMR scans were performed on more than 30 cases with broad spectrum of neurologic diseases using saturation-recovery and inversion-recovery sequences with a field strength of 1500 Gauss. Selective excitation sequence was used for the slice selection and filtered backprojection was used to reconstruct the images. They were displayed on a 256 x 256 matrix as 12 mm thick sections. Data aquisition time varied between 3 and 12 minutes. Our initial experiences with six cases harboring cerebellopontine angle lesions discolsed advantages and disadvantages of NMR imaging in comparison with X-ray CT. The advantages were the absence of linear artifacts from the surrounding bone, the marked gray-white matter differentiation, and the variety of tomographic planes available. The disadvantages included the lack of bone detail, the lack of visualization of the major intracranial vessels, and the long time required for scanning (several minutes per slice). Although much continued evaluation is necessary, NMR seems to have vast potential as a diagnostic tool. (author)

  3. 13. Nuclear magnetic resonance users meeting. Extended abstracts book

    International Nuclear Information System (INIS)

    2011-01-01

    This annual meeting, held in Brazil from May 2 - 6, 2011 comprised seventeen lectures, given by invited speakers from Brazil and other countries, about the use of nuclear magnetic resonance for various analytical purposes; results from ninety five research works, most being carried out by scientific groups from various Brazilian R and D institutions, presented as congress panels/posters. A General Assembly meeting of AUREMN, the Brazilian Association of Nuclear Magnetic Resonance Users, also took place during the event. Main topics of the research works presented at this meeting were thus distributed: 54% in analytical chemistry (mainly organic chemistry, both experimental and theoretical works), 18% in applied life sciences (agricultural and food sciences, biological sciences and medicine), 15% in materials science (including nanostructures, petroleum and alternative fuels), 10% in mathematical methods and computing for the interpretation of NMR data, and the remaining 3% in improvements in instrumentation interfaces or magnetic field configurations.

  4. The origins and future of nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Wehrli, F.W.

    1992-01-01

    What began as a curiosity of physics has become the preeminent method of diagnostic medical imaging and may displace x-ray-based techniques in the 21st century. During the past two decades nuclear magnetic resonance has revolutionized chemistry, biochemistry, biology and, more recently, diagnostic medicine. Nuclear magnetic resonance imaging, (MRI) as it is commonly called, is fundamentally different from x-ray-based techniques in terms of the principles of spatial encoding and mechanisms of signal and contrast generation involved. MRI has a far richer ultimate potential than any other imaging technique known today, and its technology and applications are still far from maturation, which may not occur until early in the 21st century. 23 refs., 6 figs

  5. 13. Nuclear magnetic resonance users meeting. Extended abstracts book

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    This annual meeting, held in Brazil from May 2 - 6, 2011 comprised seventeen lectures, given by invited speakers from Brazil and other countries, about the use of nuclear magnetic resonance for various analytical purposes; results from ninety five research works, most being carried out by scientific groups from various Brazilian R and D institutions, presented as congress panels/posters. A General Assembly meeting of AUREMN, the Brazilian Association of Nuclear Magnetic Resonance Users, also took place during the event. Main topics of the research works presented at this meeting were thus distributed: 54% in analytical chemistry (mainly organic chemistry, both experimental and theoretical works), 18% in applied life sciences (agricultural and food sciences, biological sciences and medicine), 15% in materials science (including nanostructures, petroleum and alternative fuels), 10% in mathematical methods and computing for the interpretation of NMR data, and the remaining 3% in improvements in instrumentation interfaces or magnetic field configurations.

  6. Resonating-group method for nuclear many-body problems

    International Nuclear Information System (INIS)

    Tang, Y.C.; LeMere, M.; Thompson, D.R.

    1977-01-01

    The resonating-group method is a microscopic method which uses fully antisymmetric wave functions, treats correctly the motion of the total center of mass, and takes cluster correlation into consideration. In this review, the formulation of this method is discussed for various nuclear many-body problems, and a complex-generator-coordinate technique which has been employed to evaluate matrix elements required in resonating-group calculations is described. Several illustrative examples of bound-state, scattering, and reaction calculations, which serve to demonstrate the usefulness of this method, are presented. Finally, by utilization of the results of these calculations, the role played by the Pauli principle in nuclear scattering and reaction processes is discussed. 21 figures, 2 tables, 185 references

  7. E2 nuclear resonance effects in pionic and kaonic atoms

    International Nuclear Information System (INIS)

    Batty, C.J.; Biagi, S.F.; Blecher, M.

    1977-09-01

    The attenuation due to the E2 nuclear resonance effect has been measured in hadronic atoms using pions with 111 Cd and 112 Cd, and for kaons with 122 Sn. Energies of the relevant X-ray and γ-ray transitions and of the X-ray cascade intensities have also been measured so as to give a self-consistent set of information. The results are found to be in very good agreement with theoretical calculations. (author)

  8. Nuclear magnetic resonance imaging and brain functional exploration

    International Nuclear Information System (INIS)

    Le Bihan, D.; CEA, 91 - Orsay

    1997-01-01

    The utilization of nuclear magnetic resonance imaging for functional analysis of the brain is presented: the oxygenated and deoxygenated blood flowing in the brain do not have the same effect on NMR images; the oxygenated blood, related to brain activity, may be detected and the corresponding activity zone in the brain, identified; functional NMR imaging could be used to gain a better understanding of functional troubles linked to neurological or psychiatric diseases

  9. Nuclear Magnetic Resonance, a Powerful Tool in Cultural Heritage

    OpenAIRE

    Noemi Proietti; Donatella Capitani; Valeria Di Tullio

    2018-01-01

    In this paper five case studies illustrating applications of NMR (Nuclear Magnetic Resonance) in the field of cultural heritage, are reported. Different issues were afforded, namely the investigation of advanced cleaning systems, the quantitative mapping of moisture in historic walls, the investigation and evaluation of restoration treatments on porous stones, the stratigraphy of wall paintings, and the detection of CO2 in lapis lazuli. Four of these case studies deal with the use of portable...

  10. Resonance and nuclear relaxation in GdCo2

    International Nuclear Information System (INIS)

    Barata, A.C.

    1988-04-01

    A study of the 59 Co nuclear magnetic resonance and relaxation was made on the intermetallic compound GdCo 2 from 4,2 k to 330 k using the spin echo technique. An oscillatory behaviour of the primary echo was observed in the whole range of temperatures studied. This is due to the electronic quadrupole interaction of the 59 Co nuclei. (A.C.A.S.) [pt

  11. Display of cross sectional anatomy by nuclear magnetic resonance imaging.

    Science.gov (United States)

    Hinshaw, W S; Andrew, E R; Bottomley, P A; Holland, G N; Moore, W S

    1978-04-01

    High definition cross-sectional images produced by a new nuclear magnetic resonance (NMR) technique are shown. The images are a series of thin section scans in the coronal plane of the head of a rabbit. The NMR images are derived from the distribution of the density of mobile hydrogen atoms. Various tissue types can be distinguished and a clear registration of gross anatomy is demonstrated. No known hazards are associated with the technique.

  12. Nuclear magnetic resonance tomography in Hallervorden-Spatz's syndrome

    International Nuclear Information System (INIS)

    Vogl, T.; Bauer, M.; Seiderer, M.; Rath, M.

    1984-01-01

    Two patients (mother and son) with Hallervorden-Spatz's syndrome were examined both via CT and Nuclear Magnetic Resonance (NMR), using different measuring modes. In the patient with progressing disease pathological findings were seen in the right and left putamen with CT and NMR. All examinations in the mother with a less progressive syndrome were without any result. Information obtained via NMR did not yield significantly more relevant data than computed tomography. (orig.) [de

  13. Nuclear resonance vibrational spectroscopic studies of iron-containing biomolecules

    International Nuclear Information System (INIS)

    Ohta, Takehiro; Seto, Makoto

    2014-01-01

    In this review, we report recent nuclear resonance vibrational spectroscopic (NRVS) studies of iron-containing biomolecules and their model complexes. The NRVS is synchrotron-based element-specific vibrational spectroscopic methods. Unlike Raman and infrared spectroscopy, the NRVS can investigate all iron motions without selection rules, which provide atomic level insights into the structure/reactivity correlation of biologically relevant iron complexes. (author)

  14. Low-frequency nuclear quadrupole resonance with a dc SQUID

    International Nuclear Information System (INIS)

    Chang, J.W.

    1991-07-01

    Conventional pure nuclear quadrupole resonance (NQR) is a technique well suited for the study of very large quadrupolar interactions. Numerous nuclear magnetic resonance (NMR) techniques have been developed for the study of smaller quadrupolar interactions. However, there are many nuclei which have quadrupolar interactions of intermediate strength. Quadrupolar interactions in this region have traditionally been difficult or unfeasible to detect. This work describes the development and application of a SQUID NQR technique which is capable of measuring intermediate strength quadrupolar interactions, in the range of a few hundred kilohertz to several megahertz. In this technique, a dc SQUID (Superconducting QUantum Interference Device) is used to monitor the longitudinal sample magnetization, as opposed to the transverse magnetization, as a rf field is swept in frequency. This allows the detection of low-frequency nuclear quadrupole resonances over a very wide frequency range with high sensitivity. The theory of this NQR technique is discussed and a description of the dc SQUID system is given. In the following chapters, the spectrometer is discussed along with its application to the study of samples containing half-odd-integer spin quadrupolar nuclei, in particular boron-11 and aluminum-27. The feasibility of applying this NQR technique in the study of samples containing integer spin nuclei is discussed in the last chapter. 140 refs., 46 figs., 6 tabs

  15. The design of photoelectric signal processing system for a nuclear magnetic resonance gyroscope based on FPGA

    Science.gov (United States)

    Zhang, Xian; Zhou, Binquan; Li, Hong; Zhao, Xinghua; Mu, Weiwei; Wu, Wenfeng

    2017-10-01

    Navigation technology is crucial to the national defense and military, which can realize the measurement of orientation, positioning, attitude and speed for moving object. Inertial navigation is not only autonomous, real-time, continuous, hidden, undisturbed but also no time-limited and environment-limited. The gyroscope is the core component of the inertial navigation system, whose precision and size are the bottleneck of the performance. However, nuclear magnetic resonance gyroscope is characteristic of the advantage of high precision and small size. Nuclear magnetic resonance gyroscope can meet the urgent needs of high-tech weapons and equipment development of new generation. This paper mainly designs a set of photoelectric signal processing system for nuclear magnetic resonance gyroscope based on FPGA, which process and control the information of detecting laser .The photoelectric signal with high frequency carrier is demodulated by in-phase and quadrature demodulation method. Finally, the processing system of photoelectric signal can compensate the residual magnetism of the shielding barrel and provide the information of nuclear magnetic resonance gyroscope angular velocity.

  16. Nuclear magnetic resonance. Advanced concepts and applications to quantum materials

    International Nuclear Information System (INIS)

    Kohlrautz, Jonas

    2017-01-01

    In this thesis, three separate topics were presented. These include the development of novel experimental NMR methods and data analysis, as well as their application to current topics of condensed matter research. The first part concerns NMR at the highest magnetic fields, i.e., in time-dependent pulsed high-field magnets. After a discussion of consequences for NMR, a method to acquire broad spectra was presented. Here, an intensity-correction for off-resonance effects was applied and the Fourier transform was modified to use time-dependent base functions. Subsequently, the method was tested with a Knight shift measurement of metallic aluminum using a second compound as a shift reference. It could be shown that signal averaging of a weak signal is possible, even across multiple field pulses. Thus, in principle, the signal-to-noise ratio can always be increased at the cost of measurement time, despite the inherently limited reproducibility of subsequent field high-field pulses. In another set of experiments, the feasibility of T 1 measurements was shown. Here, a weak radio frequency field was used to perform an adiabatic inversion of the spin system in the time-dependent field. Ensuing small-angle RF pulses monitored the relaxation process. Using a mathematical model, T 1 was then determined. Finally, this method was applied for the investigation of the spin-dimer antiferromagnet SrCu 2 (BO 3 ) 2 . Evidence for a field-induced change in the ground state of the material was found. This appears to be the first convincing observation of a field-induced phenomenon with pulsed field NMR. It proves that nuclear magnetic resonance spectroscopy at the highest fields is able to produce unique insights into quantum materials. The second part of the thesis concerns NMR investigations and analysis of cuprate high-temperature superconductors in conventional static field measurements. Results on HgBa 2 CuO 4+δ for underdoped, optimally doped, and overdoped materials revealed

  17. Nuclear magnetic resonance. Advanced concepts and applications to quantum materials

    Energy Technology Data Exchange (ETDEWEB)

    Kohlrautz, Jonas

    2017-05-22

    In this thesis, three separate topics were presented. These include the development of novel experimental NMR methods and data analysis, as well as their application to current topics of condensed matter research. The first part concerns NMR at the highest magnetic fields, i.e., in time-dependent pulsed high-field magnets. After a discussion of consequences for NMR, a method to acquire broad spectra was presented. Here, an intensity-correction for off-resonance effects was applied and the Fourier transform was modified to use time-dependent base functions. Subsequently, the method was tested with a Knight shift measurement of metallic aluminum using a second compound as a shift reference. It could be shown that signal averaging of a weak signal is possible, even across multiple field pulses. Thus, in principle, the signal-to-noise ratio can always be increased at the cost of measurement time, despite the inherently limited reproducibility of subsequent field high-field pulses. In another set of experiments, the feasibility of T{sub 1} measurements was shown. Here, a weak radio frequency field was used to perform an adiabatic inversion of the spin system in the time-dependent field. Ensuing small-angle RF pulses monitored the relaxation process. Using a mathematical model, T{sub 1} was then determined. Finally, this method was applied for the investigation of the spin-dimer antiferromagnet SrCu{sub 2}(BO{sub 3}){sub 2}. Evidence for a field-induced change in the ground state of the material was found. This appears to be the first convincing observation of a field-induced phenomenon with pulsed field NMR. It proves that nuclear magnetic resonance spectroscopy at the highest fields is able to produce unique insights into quantum materials. The second part of the thesis concerns NMR investigations and analysis of cuprate high-temperature superconductors in conventional static field measurements. Results on HgBa{sub 2}CuO{sub 4+δ} for underdoped, optimally doped, and

  18. DC superconducting quantum interference device usable in nuclear quadrupole resonance and zero field nuclear magnetic spectrometers

    Science.gov (United States)

    Fan, Non Q.; Clarke, John

    1993-01-01

    A spectrometer for measuring the nuclear quadrupole resonance spectra or the zero-field nuclear magnetic resonance spectra generated by a sample is disclosed. The spectrometer uses an amplifier having a dc SQUID operating in a flux-locked loop for generating an amplified output as a function of the intensity of the signal generated by the sample. The flux-locked loop circuit includes an integrator. The amplifier also includes means for preventing the integrator from being driven into saturation. As a result, the time for the flux-locked loop to recover from the excitation pulses generated by the spectrometer is reduced.

  19. Nuclear performance standards: Promoting efficient generation

    International Nuclear Information System (INIS)

    Nagelhout, M.

    1990-01-01

    Nuclear plant performance standards are designed to share the risks of operation associated with nuclear generation. Such standards often shift risks from ratepayers to utility shareholders, even without a finding of imprudence or mismanagement. The rationale underlying nuclear performance standards is that ratepayers should not be responsible for excessive replacement power costs incurred as a result of unreasonable decisions by utility management, especially because the high fixed costs of nuclear plants are already included in base rates. In addition, performance standards can be designed to provide incentives to reward utilities that achieve superior nuclear performance, for the benefit of both ratepayers and shareholders

  20. High resolution spectroscopy in solids by nuclear magnetic resonance; Espectroscopia de alta resolucao em solidos por ressonancia magnetica nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Bonagamba, T J

    1991-07-01

    The nuclear magnetic resonance (NMR) techniques for High Resolution Spectroscopy in Solids are described. Also the construction project of a partially home made spectrometer and its applications in the characterization of solid samples are shown in detail. The high resolution spectrometer used is implemented with the double resonance multiple pulses sequences and magic angle spinning (MAS) and can be used with solid and liquid samples. The maximum spinning frequency for the MAS experiment is in excess of 5 Khz, the double resonance sequences can be performed with any type of nucleus, in the variable temperature operating range with nitrogen gas: -120{sup 0} C to +160{sup 0} C, and is fully controlled by a Macintosh IIci microcomputer. (author).

  1. Phosphorus nuclear magnetic resonance in isolated perfused rat pancreas

    International Nuclear Information System (INIS)

    Matsumoto, Takehisa; Kanno, Tomio; Seo, Yoshiteru; Murakami, Masataka; Watari, Hiroshi

    1988-01-01

    Phosphorus nuclear magnetic resonance spectroscopy was applied to measure phosphorus energy metabolites in isolated perfused rat pancreas. The gland was perfused with a modified Krebs-Henseleit solution at room temperature (25 degree C). 31 P resonances of creatine phosphate (PCr), ATP, ADP, inorganic phosphate (P i ) and phosphomonoesters (PMEs) were observed in all the preparations of pancreas. In different individual preparations, the resonance of PCr varied, but those of ATP were almost the same. The initial levels of PCr and ATP in individual preparations, however, remained almost unchanged during perfusion with the standard solution for 2 h. When the perfusion was stopped, the levels of ATP and PCr decreased, while the levels of PME and P i increased. At that time, the P i resonance shfted to a higher magnetic field, indicating that the tissue pH decreased. On reperfusion, the tissue levels of phosphorus compounds and the tissue pH were restored to their initial resting levels. Continuous infusion of 0.1 μM acetylcholine caused marked and sustained increases in the flow of pancreatic juice and protein output. During the stimulation the tissue levels of phosphorus compounds remained unchanged, while the tissue pH was decreased slightly

  2. Nuclear data adjustment methodology utilizing resonance parameter sensitivities and uncertainties

    International Nuclear Information System (INIS)

    Broadhead, B.L.

    1983-01-01

    This work presents the development and demonstration of a Nuclear Data Adjustment Method that allows inclusion of both energy and spatial self-shielding into the adjustment procedure. The resulting adjustments are for the basic parameters (i.e. resonance parameters) in the resonance regions and for the group cross sections elsewhere. The majority of this development effort concerns the production of resonance parameter sensitivity information which allows the linkage between the responses of interest and the basic parameters. The resonance parameter sensitivity methodology developed herein usually provides accurate results when compared to direct recalculations using existng and well-known cross section processing codes. However, it has been shown in several cases that self-shielded cross sections can be very non-linear functions of the basic parameters. For this reason caution must be used in any study which assumes that a linear relatonship exists between a given self-shielded group cross section and its corresponding basic data parameters. The study also has pointed out the need for more approximate techniques which will allow the required sensitivity information to be obtained in a more cost effective manner

  3. Proceedings of the 37. Polish Seminar on Nuclear Magnetic Resonance and its Applications

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-11-01

    37. Polish Seminar on Nuclear Magnetic Resonance and Its Applications is Cyclically organised forum for discussing the actual problems, achievements and perspectives of methodology and interpretation of NMR. At presenting edition the problems of NMR imaging in medicine diagnostics, studies of biologically important organic molecules as well as inorganic compounds being interesting for microelectronics and catalysis have been especially emphasized. The progress in computerized simulation for NMR spectra interpretation has been also performed in numerous presentations.

  4. Proceedings of the 37. Polish Seminar on Nuclear Magnetic Resonance and its Applications

    International Nuclear Information System (INIS)

    2004-11-01

    37. Polish Seminar on Nuclear Magnetic Resonance and Its Applications is Cyclically organised forum for discussing the actual problems, achievements and perspectives of methodology and interpretation of NMR. At presenting edition the problems of NMR imaging in medicine diagnostics, studies of biologically important organic molecules as well as inorganic compounds being interesting for microelectronics and catalysis have been especially emphasized. The progress in computerized simulation for NMR spectra interpretation has been also performed in numerous presentations

  5. Prototype explosives detection system based on nuclear resonance absorption in nitrogen

    International Nuclear Information System (INIS)

    Morgado, R.E.; Arnone, G.J.; Cappiello, C.C.

    1996-01-01

    A laboratory prototype system has been developed for the experimental evaluation of an explosives detection technique based on nuclear resonance absorption of gamma rays in nitrogen. Major subsystems include a radiofrequency quadrupole proton accelerator and associated beam transport system, a high-power gamma-ray production target, an airline-luggage tomographic inspection system, and an image- processing/detection-alarm subsystem. The detection system performance, based on a limited experimental test, is reported

  6. Zero Quantum Nuclear Magnetic Resonance experiments utilizing a toroid cell and coil

    OpenAIRE

    Bebout, William Roach

    1989-01-01

    Over the past ten to fifteen years the area of Nuclear Magnetic Resonance (NMR) Spectroscopy has seen tremendous growth. For example, in conjunction with multiple quantum NMR, molecular structural mapping of a compound can be easily performed in a two dimensional (2D) experiment. However, only two kinds of detector coils have been typically used in NMR studies. These are the solenoid coil and the Helmholtz coil. The solenoid coil was very popular with the permanent and e...

  7. Solid state nuclear magnetic resonance: investigating the spins of nuclear related materials

    International Nuclear Information System (INIS)

    Charpentier, Th.

    2007-10-01

    The author reviews his successive research works: his research thesis work on the Multiple Quantum Magic Angle Spinning (MQMAS) which is a quadric-polar nucleus multi-quanta correlation spectroscopy method, the modelling of NMR spectra of disordered materials, the application to materials of interest for the nuclear industry (notably the glasses used for nuclear waste containment). He presents the various research projects in which he is involved: storing glasses, nuclear magnetic resonance in paramagnetism, solid hydrogen storing matrices, methodological and instrument developments in high magnetic field and high resolution solid NMR, long range distance measurement by solid state Tritium NMR (observing the structure and dynamics of biological complex systems at work)

  8. Nuclear magnetic resonance imaging of the central nervous system

    International Nuclear Information System (INIS)

    Knaap, M.S. van der; Valk, J.

    1989-01-01

    In this article a review is given of the use of magnetic resonance imaging for the central nervous system. An example of the screening of the population for multiple scelerosis is given. A good preliminary examination and the supply of relevant information to the person which performs the imaging is necessary. (R.B.). 9 figs.; 4 tabs

  9. Applications of nuclear magnetic resonance spectroscopy to certifiable food colors

    International Nuclear Information System (INIS)

    Marmion, D.M.

    Nuclear magnetic resonance spectroscopy was found suitable for the identification of individual colours, for distinguishing individual colours from colour mixtures, for the identification and semi-quantitative determination of the individual colours in mixtures and for proofs of the adulteration of certified colours adding noncertified colours. The method is well suited for observing the purity of colours and may also be used as the control method in the manufacture of colours and in assessing their stability and their resistance to increased temperature and light. (M.K.)

  10. Nuclear magnetic resonance characterization of apple juice containing enzyme preparations

    International Nuclear Information System (INIS)

    Prestes, Rosilene A.; Almeida, Denise Milleo; Barison, Andersson; Pinheiro, Luis Antonio; Wosiacki, Gilvan

    2012-01-01

    In this work, 1 H nuclear magnetic resonance ( 1 H NMR) was employed to evaluate changes in apple juice in response to the addition of Panzym Yieldmash and Ultrazym AFP-L enzymatic complexes and compare it with premium apple juice. The juice was processed at different temperatures and concentrations of enzymatic complexes. The differences in the results were attributed mainly to the enzyme concentrations, since temperature did not cause any variation. A quantitative analysis indicated that the concentration of fructose increased while the concentrations of sucrose and glucose decreased in response to increasing concentrations of the enzymatic complexes. (author)

  11. Implementation of Quantum Private Queries Using Nuclear Magnetic Resonance

    International Nuclear Information System (INIS)

    Wang Chuan; Hao Liang; Zhao Lian-Jie

    2011-01-01

    We present a modified protocol for the realization of a quantum private query process on a classical database. Using one-qubit query and CNOT operation, the query process can be realized in a two-mode database. In the query process, the data privacy is preserved as the sender would not reveal any information about the database besides her query information, and the database provider cannot retain any information about the query. We implement the quantum private query protocol in a nuclear magnetic resonance system. The density matrix of the memory registers are constructed. (general)

  12. Applications of Nuclear Magnetic Resonance Sensors to Cultural Heritage

    Directory of Open Access Journals (Sweden)

    Noemi Proietti

    2014-04-01

    Full Text Available In recent years nuclear magnetic resonance (NMR sensors have been increasingly applied to investigate, characterize and monitor objects of cultural heritage interest. NMR is not confined to a few specific applications, but rather its use can be successfully extended to a wide number of different cultural heritage issues. A breakthrough has surely been the recent development of portable NMR sensors which can be applied in situ for non-destructive and non-invasive investigations. In this paper three studies illustrating the potential of NMR sensors in this field of research are reported.

  13. Nuclear Magnetic Resonance, a Powerful Tool in Cultural Heritage

    Directory of Open Access Journals (Sweden)

    Noemi Proietti

    2018-01-01

    Full Text Available In this paper five case studies illustrating applications of NMR (Nuclear Magnetic Resonance in the field of cultural heritage, are reported. Different issues were afforded, namely the investigation of advanced cleaning systems, the quantitative mapping of moisture in historic walls, the investigation and evaluation of restoration treatments on porous stones, the stratigraphy of wall paintings, and the detection of CO2 in lapis lazuli. Four of these case studies deal with the use of portable NMR sensors which allow non-destructive and non-invasive investigation in situ. The diversity among cases reported demonstrates that NMR can be extensively applied in the field of cultural heritage.

  14. Transistor regenerative spectrometer for 14N nuclear quadrupole resonance study

    International Nuclear Information System (INIS)

    Anferov, V.P.; Mikhal'kov, V.M.

    1981-01-01

    Improvement of the Robinson transducer for investigations of nuclear quadrupole resonance (NQR) in 14 N is described. Amplifier of the suggested transducer is made using p-n field effect transistor and small-noise SHF bipolar transistor. Such a circuit permits to obtain optimal relation between input resistance, low-frequency noises and transconductance which provides uniform gain of the transducer in the frequency range of 0.6-12 MHz and permits to construct a transistor spectrometer of NQR not yielding to a lamp spectrometer in sensitivity [ru

  15. Nuclear magnetic resonance. Applications to medicine and biology

    International Nuclear Information System (INIS)

    Berdugo, M.; Fauchet, M.; Menasche, P.; Grall, Y.; Piwnica, A.

    1982-01-01

    Nuclear magnetic resonance (NMR) is a non-invasive exploratory technique based on a principle radically different from those of radiography, radionuclide exploration and ultrasonography. Signals coming from atomic nuclei and reflecting their density and chemical/biochemical environment are collected, thus providing information on the physiological and pathological state of tissues. The technique has multiple applications, either practical (tomographic imaging of the brain, thyroid gland and liver) or in the field of research, e.g. investigating ischaemic myocardial areas and pathological fluid composition, measuring intracellular pH, diagnosing the nature of a tumour and, broadly speaking, understanding the biochemical changes associated with malignant degeneration [fr

  16. Nuclear-magnetic-resonance quantum calculations of the Jones polynomial

    International Nuclear Information System (INIS)

    Marx, Raimund; Spoerl, Andreas; Pomplun, Nikolas; Schulte-Herbrueggen, Thomas; Glaser, Steffen J.; Fahmy, Amr; Kauffman, Louis; Lomonaco, Samuel; Myers, John M.

    2010-01-01

    The repertoire of problems theoretically solvable by a quantum computer recently expanded to include the approximate evaluation of knot invariants, specifically the Jones polynomial. The experimental implementation of this evaluation, however, involves many known experimental challenges. Here we present experimental results for a small-scale approximate evaluation of the Jones polynomial by nuclear magnetic resonance (NMR); in addition, we show how to escape from the limitations of NMR approaches that employ pseudopure states. Specifically, we use two spin-1/2 nuclei of natural abundance chloroform and apply a sequence of unitary transforms representing the trefoil knot, the figure-eight knot, and the Borromean rings. After measuring the nuclear spin state of the molecule in each case, we are able to estimate the value of the Jones polynomial for each of the knots.

  17. Parahydrogen-enhanced zero-field nuclear magnetic resonance

    Science.gov (United States)

    Theis, T.; Ganssle, P.; Kervern, G.; Knappe, S.; Kitching, J.; Ledbetter, M. P.; Budker, D.; Pines, A.

    2011-07-01

    Nuclear magnetic resonance, conventionally detected in magnetic fields of several tesla, is a powerful analytical tool for the determination of molecular identity, structure and function. With the advent of prepolarization methods and detection schemes using atomic magnetometers or superconducting quantum interference devices, interest in NMR in fields comparable to the Earth's magnetic field and below (down to zero field) has been revived. Despite the use of superconducting quantum interference devices or atomic magnetometers, low-field NMR typically suffers from low sensitivity compared with conventional high-field NMR. Here we demonstrate direct detection of zero-field NMR signals generated through parahydrogen-induced polarization, enabling high-resolution NMR without the use of any magnets. The sensitivity is sufficient to observe spectra exhibiting 13C-1H scalar nuclear spin-spin couplings (known as J couplings) in compounds with 13C in natural abundance, without the need for signal averaging. The resulting spectra show distinct features that aid chemical fingerprinting.

  18. Application of nuclear resonance scattering for in vivo measurements

    International Nuclear Information System (INIS)

    Wielopolski, L.; Vartsky, D.; Cohn, S.H.

    1983-01-01

    Nuclear resonance scattering is applied in our laboratory to measure hepatic and cardiac iron overload. For iron analysis, a gaseous source of 4 mg MnCl 2 is introduced into an evacuated quartz vial. Following irradiation in a nuclear reactor, 56 Mn decays by beta emission to the 847-keV level of 56 Fe, which subsequently decays to the ground state of 56 Fe with a 7 ps half-life. The principal aim of this work is to evaluate the efficacy of the iron chelation therapy. Serial measurements over a time period of 6 to 12 months of a given patient will enable us to see how the iron is removed from the critical organs

  19. Capacitor-based detection of nuclear magnetization: nuclear quadrupole resonance of surfaces.

    Science.gov (United States)

    Gregorovič, Alan; Apih, Tomaž; Kvasić, Ivan; Lužnik, Janko; Pirnat, Janez; Trontelj, Zvonko; Strle, Drago; Muševič, Igor

    2011-03-01

    We demonstrate excitation and detection of nuclear magnetization in a nuclear quadrupole resonance (NQR) experiment with a parallel plate capacitor, where the sample is located between the two capacitor plates and not in a coil as usually. While the sensitivity of this capacitor-based detection is found lower compared to an optimal coil-based detection of the same amount of sample, it becomes comparable in the case of very thin samples and even advantageous in the proximity of conducting bodies. This capacitor-based setup may find its application in acquisition of NQR signals from the surface layers on conducting bodies or in a portable tightly integrated nuclear magnetic resonance sensor. Copyright © 2010 Elsevier Inc. All rights reserved.

  20. Study of γ-irradiated lithographic polymers by electron spin resonance and electron nuclear double resonance

    International Nuclear Information System (INIS)

    Schlick, S.; Kevan, L.

    1982-01-01

    The room temperature gamma irradiation degradation of the lithographic polymers, poly(methylmethacrylate) (PMMA), poly(methyl-α-chloroacrylate) (PMCA), poly(methyl-α-fluoroacrylate) (PMFA), and poly(methylacrylonitrile) (PMCN), have been studied by electron spin resonance and electron nuclear double resonance (ENDOR) to assess their molecular degradation processes of relevance to electron beam lithography. Two classes of radicals are found, chain radicals and chain scission radicals. PMMA and PMCA mainly form chain scission radicals consistent with degradation while for PMCN the resolution is poorer, and this is only probable. PMFA forms mainly chain radicals consistent with predominant crosslinking. The total radical yield is greatest in PMCA and PMCN. ENDOR is used to assess the compactness of the radiation degradation region for PMMA and PMCA and hence the potential resolution of the resist; this appears to be about the same for these methacrylate polymers

  1. Rotating-frame gradient fields for magnetic resonance imaging and nuclear magnetic resonance in low fields

    Science.gov (United States)

    Bouchard, Louis-Serge; Pines, Alexander; Demas, Vasiliki

    2014-01-21

    A system and method for Fourier encoding a nuclear magnetic resonance (NMR) signal is disclosed. A static magnetic field B.sub.0 is provided along a first direction. An NMR signal from the sample is Fourier encoded by applying a rotating-frame gradient field B.sub.G superimposed on the B.sub.0, where the B.sub.G comprises a vector component rotating in a plane perpendicular to the first direction at an angular frequency .omega.in a laboratory frame. The Fourier-encoded NMR signal is detected.

  2. The isoscalar giant dipole resonance and nuclear incompressibility

    International Nuclear Information System (INIS)

    Garg, U.

    2000-01-01

    Complete text of publication follows. The current status of the experimental work on the ISOSCALAR giant dipole resonance (ISGDR) will be reviewed. ISGDR is an exotic mode of collective nuclear vibration and can be described as a hydrodynamical density oscillation in which the volume of the nucleus remains constant and the state can be visualized in the form of a compression wave-analogous to a sound wave-oscillating back and forth through the nucleus. [1] Convincing evidence for the ISGDR has now been obtained in inelastic α-scattering measurements at 200 MeV (IUCF) [2], 240 MeV (Texas A and M) [3] and 400 MeV (RCNP, Osaka) [4]. In all nuclei studied so far, the ISGDR strength is observed to be spread over a rather wide excitation-energy range (up to ∼ 15 MeV). The excitation energy of the ISGDR is related to the nuclear incompressibility, K ∞ . The ISGDR results so far point to a value for K ∞ that is ∼ 30-40% lower than the obtained from the energies of the other compressional mode, the giant monopole resonance. Results from recent theoretical attempts to reconcile this difference will be presented. This work has been supported in part by the U.S. National Science Foundation. (author)

  3. Resonant Electromagnetic Interaction in Low Energy Nuclear Reactions

    Science.gov (United States)

    Chubb, Scott

    2008-03-01

    Basic ideas about how resonant electromagnetic interaction (EMI) can take place in finite solids are reviewed. These ideas not only provide a basis for conventional, electron energy band theory (which explains charge and heat transport in solids), but they also explain how through finite size effects, it is possible to create many of the kinds of effects envisioned by Giuliano Preparata. The underlying formalism predicts that the orientation of the external fields in the SPAWAR protocolootnotetextKrivit, Steven B., New Energy Times, 2007, issue 21, item 10. http://newenergytimes.com/news/2007/NET21.htm^,ootnotetextSzpak, S.; Mosier-Boss, P.A.; Gordon, F.E. Further evidence of nuclear reactions in the Pd lattice: emission of charged particles. Naturwissenschaften 94,511(2007)..has direct bearing on the emission of high-energy particles. Resonant EMI also implies that nano-scale solids, of a particular size, provide an optimal environment for initiating Low Energy Nuclear Reactions (LENR) in the PdD system.

  4. Triple aldose reductase/α-glucosidase/radical scavenging high-resolution profiling combined with high-performance liquid chromatography – high-resolution mass spectrometry – solid-phase extraction – nuclear magnetic resonance spectroscopy for identification of antidiabetic constituents in crude, extract of Radix Scutellariae

    DEFF Research Database (Denmark)

    Tahtah, Yousof; Kongstad, Kenneth Thermann; Wubshet, Sileshi Gizachew

    2015-01-01

    high-performance liquid chromatography – high-resolution mass spectrometry – solid-phase extraction – nuclear magnetic resonance spectroscopy. The only α-glucosidase inhibitor was baicalein, whereas main aldose reductase inhibitors in the crude extract were baicalein and skullcapflavone II, and main....../α-glucosidase/radical scavenging high-resolution inhibition profile - allowing proof of concept with Radix Scutellariae crude extract as a polypharmacological herbal drug. The triple bioactivity high-resolution profiles were used to pinpoint bioactive compounds, and subsequent structure elucidation was performed with hyphenated...

  5. Electron spin resonance (ESR), electron nuclear double resonance (ENDOR) and general triple resonance of irradiated biocarbonates

    International Nuclear Information System (INIS)

    Schramm, D.U.; Rossi, A.M.

    1996-01-01

    Several irradiated bicarbonates were studied by magnetic resonance techniques. Seven paramagnetic species, attributed to CO 2 - , SO 2 - and SO 3 - were identified. Comparison between radiation induced defects in bioaragonites and aragonite single-crystals show that isotropic and orthorhombic CO 2 - centers with broad line spectra are not produced in the latter samples. Vibrational and rotational properties of isotropic CO 2 - centers were studied from low temperature Q-band spectras. Vibrational frequency is determined from the 13 CO 2 - hyperfine spectrum and yielded ν 1.54 x 10 13 s -1 . The correlation time for isotropic CO 2 - , τc) = 1.2 x 10 -11 s (T = 300 K0, is typical of radicals rotating in liquids. ENDOR and General Triple spectroscopy show that orthorhombic CO 2 - centres are surrounded by water molecules located in the second nearest CO 2 2- sites at 5.14, 5.35 and 6.02 A. Water molecules replacing carbonates or as liquid inclusion of growth solution in local crystal imperfections may be responsible for the variety of orthorhombic and isotropic CO 2 - species, respectively. (author)

  6. Investigating resonances above and below the threshold in nuclear reactions of astrophysical interest and beyond

    Energy Technology Data Exchange (ETDEWEB)

    La Cognata, M., E-mail: lacognata@lns.infn.it [Laboratori Nazionali del Sud - INFN, Catania (Italy); Kiss, G. G. [ATOMKI, Debrecen (Hungary); Mukhamedzhanov, A. M. [Cyclotron Institute, Texas A& M University, College Station, Texas (United States); Spitaleri, C. [Laboratori Nazionali del Sud - INFN, Catania (Italy); Department of Physics and Astronomy, University of Catania, Catania (Italy); Trippella, O. [Sezione di Perugia - INFN, Perugia (Italy)

    2015-10-15

    Resonances in nuclear cross sections dramatically change their trends. Therefore, the presence of unexpected resonances might lead to unpredicted consequences on astrophysics and nuclear physics. In nuclear physics, resonances allow one to study states in the intermediate compound systems, to evaluate their cluster structure, for instance, especially in the energy regions approaching particle decay thresholds. In astrophysics, resonances might lead to changes in the nucleosynthesis flow, determining different isotopic compositions of the nuclear burning ashes. For these reasons, the Trojan Horse method has been modified to investigate resonant reactions. Thanks to this novel approach, for the first time normalization to direct data might be avoided. Moreover, in the case of sub threshold resonances, the Trojan Horse method modified to investigate resonances allows one to deduce the asymptotic normalization coefficient, showing the close connection between the two indirect approaches.

  7. Nuclear statistics of dysprosium resonance parameters in the energy range 10 - 1000 eV

    International Nuclear Information System (INIS)

    Shin, S. G.; Kye, Y. U.; Cho, M. H.; Kim, G. N.; Namkung, W.; Lee, M. W.; Kang, Y. R.; Roe, T. I.

    2016-01-01

    A resonance parameter analysis is often performed in the Resolved Resonance Region (RRR) in order to estimate the average level spacing, distribution of the reduced widths and so on. Neutron Capture experiments on dysprosium isotopes were performed at the electron linear accelerator (LINAC) facility of the Rensselear Polytechnic Institute (RPI) in the neutron energy region from 10 eV to 1 keV. The following nuclear statistics of the resonance parameters will be discussed in this paper. The D 0 for 161 Dy and 163 Dy were judged to be constant up to 120.6 and 163.9 eV, respectively. It was assumed that the D 0 of 162 Dy and 164 Dy is constant up to 1000 eV because they have few resonances. The results were compared with the values from Reference 11 as shown in Figure 1. Statistical distributions of reduced neutron were investigated for the three isotopes in the region from 0 to 1000 eV; 161 Dy, 162 Dy, and 163 Dy, but not for 164 Dy because of a few number of resonances. The reduced neutron widths Γ n 0 were divided by the unweighted average reduced neutron width < Γ n 0 > for each isotope. A cumulative distribution of these unitless ratios is compared with the integral of the Porter-Thomas distribution (χ 2 distribution with one degree of freedom). The results agree reasonably with the Porter Thomas distributions.

  8. Nuclear Resonance Fluorescence off 54Cr: The Onset of the Pygmy Dipole Resonance

    Science.gov (United States)

    Ries, P. C.; Beck, T.; Beller, J.; Krishichayan; Gayer, U.; Isaak, J.; Löher, B.; Mertes, L.; Pai, H.; Pietralla, N.; Romig, C.; Savran, D.; Schilling, M.; Tornow, W.; Werner, V.; Zweidinger, M.

    2016-06-01

    Low-lying electric and magnetic dipole excitations (E1 and M1) below the neutron separation threshold, particularly the Pygmy Dipole Resonance (PDR), have drawn considerable attention in the last years. So far, mostly moderately heavy nuclei in the mass regions around A = 90 and A = 140 were examined with respect to the PDR. In the present work, the systematics of the PDR have been extended by measuring excitation strengths and parity quantum numbers of J = 1 states in lighter nuclei near A = 50 in order to gather information on the onset of the PDR. The nuclei 50,52,54Cr and 48,50Ti were examined via bremsstrahlung produced at the DArmstadt Superconducting electron Linear Accelerator (S-DALINAC) with photon energies up to 9.7 MeV with the method of nuclear resonance fluorescence. Numerous excited states were observed, many of which for the first time. The parity quantum numbers of these states have been determined at the High Intensity Gamma-ray Source (HIγS) of the Triangle Universities Nuclear Laboratory in Durham, NC, USA. Informations to the methods and the experimental setups will be provided and the results on 54Cr achieved will be discussed with respect to the onset of the PDR.

  9. Searching for illicit materials using nuclear resonance fluorescence stimulated by narrow-band photon sources

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, M.S., E-mail: johnson329@llnl.gov [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); San Jose State University, San Jose, CA 95192 (United States); Hagmann, C.A.; Hall, J.M.; McNabb, D.P. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Kelley, J.H.; Huibregtse, C. [North Carolina State University, Raleigh, NC 27695 (United States); Kwan, E.; Rusev, G.; Tonchev, A.P. [Duke University, Durham, NC 27708 (United States)

    2012-08-15

    We report the results of an experimental study of the sensitivity of two distinct classes of systems that exploit nuclear resonance fluorescence (NRF) to search for illicit materials in containers. One class of systems is based on the direct detection of NRF photons emitted from isotopes of interest. The other class infers the presence of a particular isotope by observing the preferential attenuation of resonant photons in the incident beam. We developed a detailed analytical model for both approaches. We performed experiments to test the model using depleted uranium as a surrogate for illicit material and used tungsten as a random choice for shielding. We performed the experiments at Duke University's High Intensity Gamma Source (HIGS). Using the methodology we detail in this paper one can use this model to estimate the performance of potential inspection systems in certifying containers as free of illicit materials and for detecting the presence of those same materials.

  10. Quantification of aquifer properties with surface nuclear magnetic resonance in the Platte River valley, central Nebraska, using a novel inversion method

    Science.gov (United States)

    Irons, Trevor P.; Hobza, Christopher M.; Steele, Gregory V.; Abraham, Jared D.; Cannia, James C.; Woodward, Duane D.

    2012-01-01

    Surface nuclear magnetic resonance, a noninvasive geophysical method, measures a signal directly related to the amount of water in the subsurface. This allows for low-cost quantitative estimates of hydraulic parameters. In practice, however, additional factors influence the signal, complicating interpretation. The U.S. Geological Survey, in cooperation with the Central Platte Natural Resources District, evaluated whether hydraulic parameters derived from surface nuclear magnetic resonance data could provide valuable input into groundwater models used for evaluating water-management practices. Two calibration sites in Dawson County, Nebraska, were chosen based on previous detailed hydrogeologic and geophysical investigations. At both sites, surface nuclear magnetic resonance data were collected, and derived parameters were compared with results from four constant-discharge aquifer tests previously conducted at those same sites. Additionally, borehole electromagnetic-induction flowmeter data were analyzed as a less-expensive surrogate for traditional aquifer tests. Building on recent work, a novel surface nuclear magnetic resonance modeling and inversion method was developed that incorporates electrical conductivity and effects due to magnetic-field inhomogeneities, both of which can have a substantial impact on the data. After comparing surface nuclear magnetic resonance inversions at the two calibration sites, the nuclear magnetic-resonance-derived parameters were compared with previously performed aquifer tests in the Central Platte Natural Resources District. This comparison served as a blind test for the developed method. The nuclear magnetic-resonance-derived aquifer parameters were in agreement with results of aquifer tests where the environmental noise allowed data collection and the aquifer test zones overlapped with the surface nuclear magnetic resonance testing. In some cases, the previously performed aquifer tests were not designed fully to characterize

  11. Nuclear Fusion Rate Study of a Muonic Molecule via Nuclear Threshold Resonances

    Science.gov (United States)

    Faghihi, F.; Eskandari, M. R.

    This work follows our previous calculations of the ground state binding energy, size, and the effective nuclear charge of the muonic T3 molecule, using the Born-Oppenheimer adiabatic approximation. In our past articles, we showed that the system possesses two minimum positions, the first one at the muonic distance and the second at the atomic distance. Also, the symmetric planner vibrational model assumed between the two minima and the approximated potential were calculated. Following from the previous studies, we now calculate the fusion rate of the T3 muonic molecule according to the overlap integral of the resonance nuclear compound nucleus and the molecular wave functions.

  12. Nuclear magnetic resonance in pulse radiolysis. Chemically induced dynamic nuclear polarization

    International Nuclear Information System (INIS)

    Trifunac, A.D.; Johnson, K.W.; Lowers, R.H.

    1976-01-01

    Nuclear magnetic resonance and chemically induced dynamic nuclear polarization (CIDNP) were applied to the study of pulse radiolysis. Samples were irradiated with a 3-MeV electron beam from the Argonne Van de Graaff accelerator in an EPR magnet (approximately 4000 G) which had axial holes for beam access. A fast flow system transferred the irradiated solution to the rotating 5-mm NMR sample tube. The NMR spectra of mixtures of sodium acetate and methanol were presented to demonstrate the features of the CIDNP in pulse radiolysis

  13. An absolute nuclear magnetic resonance magnetometer; Magnetometre absolu a resonance magnetique nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Salvi, A [Commisariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1961-10-15

    After an introduction in which the various work undertaken since the discovery of nuclear magnetic resonance is rapidly reviewed, the author describes briefly In the first chapter three types of NMR magnetometers, giving the advantages and disadvantages of each of them and deducing from this the design of the apparatus having the greatest number of qualities Chapter II is devoted to the crossed coil nuclear oscillator which operates continuously over a wide range (800 gamma). To avoid an error due to a carrying over the frequency, the measurement is carried out using bands of 1000 {gamma}. Chapter III deals with frequency measurements. The author describes an original arrangement which makes possible the frequency-field conversion with an accuracy of {+-} 5 x 10{sup -6}, and the differential measurement between two nuclear oscillators. The report finishes with a conclusion and a few recordings. (author) [French] Apres une introduction rappelant les divers travaux effectues en resonance magnetique nucleaire depuis sa mise en evidence, l'auteur decrit sommairement dans le premier chapitre trois types de magnetometre a R.M.N. enumerant les avantages et les inconvenients de chacun a partir desquels il projet, l'appareillage reunissant le maximum de qualites. Le chapitre II est consacre a l'oscillateur nucleaire a bobines croisees permettant un fonctionnement continu dons une large plage (800 gamma). Pour eviter une erreur due a l'entrainement de frequence, la mesure s'effectue par bandes de 1000 {gamma} chacune. Le chapitre III traite la mesure de frequence. L'auteur expose un montage original permettant la traduction frequence-champ avec une precision egale a {+-} 5.10{sup -6}, et la mesure differentielle entre deux oscillateurs nucleaires. Une conclusion et quelques enregistrements terminent ce travail. (auteur)

  14. Development of Selective Excitation Methods in Nuclear Magnetic Resonance: Investigation of Hemoglobin Oxygenation in Erythrocytes Using Proton and Phosphorus -31 Nuclear Magnetic Resonance

    Science.gov (United States)

    Fetler, Bayard Keith

    1993-01-01

    Nuclear magnetic resonance (NMR) offers a potential method for making measurements of the percent oxygenation of hemoglobin (Hb) in living tissue non-invasively. As a demonstration of the feasibility of such measurements, we measured the percent oxygenation of Hb in red blood cells (erythrocytes) using resonances in the proton-NMR (^1H-NMR) spectrum which are characteristic of oxyhemoglobin (oxy-Hb) and deoxyhemoglobin (deoxy-Hb), and are due to the unique magnetic properties of these molecules. To perform these measurements, we developed a new NMR method of selectively exciting signals in a region of interest with uniform phase and amplitude, while suppressing the signal of the water resonance. With this method, we are able to make exact calculations distinguishing between uniform phase excitation produced at large flip-angles using the non-linear properties of the Bloch equations, and uniform phase excitation produced at small flip-angles using asymmetric pulse excitation functions. We measured the percent oxygenation of three characteristic ^1H-NMR resonances of Hb: two from deoxy-Hb, originating from the N_delta H protons of histidine residue F8, which occur at different frequencies for the alpha and beta chains of Hb; and one from oxy-Hb, originating from the gamma_2 -CH_3 protons of valine residue E11. We performed experiments both on fresh erythrocytes and on erythrocytes depleted of 2,3-diphosphoglycerate (2,3-DPG), and found that oxygen is more tightly bound to Hb in the former case. In both fresh and 2,3-DPG-depleted samples, we found that: (i) from the deoxy-Hb marker resonances, there is a small but significant difference in the oxygen saturation between the alpha and beta chains; (ii) the decrease in the areas of the deoxy-Hb marker resonances correlates well with the increase in the percent oxygenation of Hb as measured optically; (iii) the area of the oxy-Hb marker resonance may be up to ~15% less than the optically measured Hb saturation. We are

  15. Multinuclear solid-state nuclear magnetic resonance of inorganic materials

    CERN Document Server

    MacKenzie, Kenneth J D

    2002-01-01

    Techniques of solid state nuclear magnetic resonance (NMR) spectroscopy are constantly being extended to a more diverse range of materials, pressing into service an ever-expanding range of nuclides including some previously considered too intractable to provide usable results. At the same time, new developments in both hardware and software are being introduced and refined. This book covers the most important of these new developments. With sections addressed to non-specialist researchers (providing accessible answers to the most common questions about the theory and practice of NMR asked by novices) as well as a more specialised and up-to-date treatment of the most important areas of inorganic materials research to which NMR has application, this book should be useful to NMR users whatever their level of expertise and whatever inorganic materials they wish to study.

  16. Evaluation of human thyroid tumors by proton nuclear magnetic resonance

    International Nuclear Information System (INIS)

    deCertaines, J.; Herry, J.Y.; Lancien, G.; Benoist, L.; Bernard, A.M.; LeClech, G.

    1982-01-01

    Proton nuclear magnetic resonance (NMR) was used in a study of 40 patients with thyroid tumors following partial or total thyroidectomy. Three patient groups were considered: those with nodules showing increased uptake, those with solitary nodules with decreased uptake, and those with multinodular goiters. Spin-lattice and spin-spin relaxation times (T 1 and T 2 ) were measured on samples of nodular and extranodular tissue from each patient. Increased T 1 and T 2 were observed for benign cold nodules, an increase in T 1 alone for nodules with increased uptake, and a wide fluctuation in T 1 and T 2 for multinodular goiters. The four cancers in the series did not show a distinctive proton NMR pattern in comparison with the other nodular structures studied. The results point to the feasibility of applying NMR techniques to the detection of thyroid disease

  17. Programmable quantum-state discriminator by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Gopinath, T.; Das, Ranabir; Kumar, Anil

    2005-01-01

    A programmable quantum-state discriminator is implemented by using nuclear magnetic resonance. We use a two-qubit spin-1/2 system, one for the data qubit and one for the ancilla (program) qubit. This device does the unambiguous (error-free) discrimination of a pair of states of the data qubit that are symmetrically located about a fixed state. The device is used to discriminate both linearly polarized states and elliptically polarized states. The maximum probability of successful discrimination is achieved by suitably preparing the ancilla qubit. It is also shown that the probability of discrimination depends on the angle of the unitary operator of the protocol and ellipticity of the data qubit state

  18. NUCLEAR MAGNETIC RESONANCE THE GELLED PRODUCT OF CANNIZZARO REACTION

    Directory of Open Access Journals (Sweden)

    Lilia Fernández-Sánchez

    2015-03-01

    Full Text Available The paper presents the nuclear magnetic resonance (NMR of proton 1H, carbon 13C and two dimensional spectrums, product of a green organic synthesis of redox on the Cannizzaro reaction. The product was reported as a tribochemical gel (heterogeneous mixture and confirmed by Infrared Spectroscopy IR, X-ray and scanning electron microscope (SEM. The results in this paper confirm its structure through various techniques of NMR and evaluate the content of sodium benzoate and benzyl alcohol in the spectroscopy sample, examining the values of the integrals on 1H NMR signals. The result of analysis indicates that benzyl alcohol (dispersed phase is in 33.44% mol in comparison with sodium benzoate content (continuous phase. These results confirm that the gel structure over time loses the dispersed phase of the benzyl alcohol producing a xerogel.

  19. Nuclear magnetic resonance imaging characteristics of gallstones in vitro

    International Nuclear Information System (INIS)

    Moon, K.L. Jr.; Hricak, H.; Margulis, A.R.; Bernhoft, R.; Way, L.W.; Filly, R.A.; Crooks, L.E.

    1983-01-01

    The nuclear magnetic resonance (NMR) imaging characteristics of gallstones of various composition from 36 patients were studied in vitro using a spin-echo imaging technique. The majority of gallstones (83%) produced no measurable NMR signal despite having a mean water content of 12% and a mean cholesterol content of 61%. Six (17%) of the stones had a weak but measurable signal in the center of the stone, which was thought to represent signal from water in clefts or pores within the stones. The mean water and cholesterol content of the stones with measurable signal did not differ significantly from that of stones with no signal. A possible explanation for these findings, based on the known NMR characteristics of solid materials, is offered

  20. Nuclear magnetic resonance tomography of the cervical canal

    Energy Technology Data Exchange (ETDEWEB)

    Terwey, B.; Koschorek, F.; Jensen, H.P.

    1985-12-01

    170 patients with suspected lesions of the cervical part of the medulla were examined using nuclear magnetic resonance (NMR) tomography. 27 cases revealed no pathological changes in the regions of the cervical medulla, the cervical canal and of the cervical spine. 143 cases produced pathological findings whose diagnoses determined therapeutical approach. Verified pathological changes comprised anomalies of the cranio-cervical junction like basilar impression and Arnold-Chiari malformation, various types of cavity formation in the cervical medulla (syringomyelia, hydromyelia), demyelinization processes, intramedullary and extramedullary tumours, intervertebral disk degeneration processes, dislocation of intervertebral disks and spondylophytes with spinal stenoses. Sagittal sections in different functional positions allowed to demonstrate the biomechanical effects of extramedullary masses on the cervical medulla. However, proven tumours could not be differentiated successfully using histological methods. Nevertheless, NMR tomography will replace invasive methods like conventional cervical myelography and CT myelography in diagnostic clarification of diseases of the cervical medulla.

  1. Nuclear magnetic resonance tomography of the cervical canal

    International Nuclear Information System (INIS)

    Terwey, B.; Koschorek, F.; Jensen, H.P.

    1985-01-01

    170 patients with suspected lesions of the cervical part of the medulla were examined using nuclear magnetic resonance (NMR) tomography. 27 cases revealed no pathological changes in the regions of the cervical medulla, the cervical canal and of the cervical spine. 143 cases produced pathological findings whose diagnoses determined therapeutical approach. Verified pathological changes comprised anomalies of the cranio-cervical junction like basilar impression and Arnold-Chiari malformation, various types of cavity formation in the cervical medulla (syringomyelia, hydromyelia), demyelinization processes, intramedullary and extramedullary tumours, intervertebral disk degeneration processes, dislocation of intervertebral disks and spondylophytes with spinal stenoses. Sagittal sections in different functional positions allowed to demonstrate the biomechanical effects of extramedullary masses on the cervical medulla. However, proven tumours could not be differentiated successfully using histological methods. Nevertheless, NMR tomography will replace invasive methods like conventional cervical myelography and CT myelography in diagnostic clarification of diseases of the cervical medulla. (orig.) [de

  2. High-resolution nuclear magnetic resonance studies of proteins.

    Science.gov (United States)

    Jonas, Jiri

    2002-03-25

    The combination of advanced high-resolution nuclear magnetic resonance (NMR) techniques with high-pressure capability represents a powerful experimental tool in studies of protein folding. This review is organized as follows: after a general introduction of high-pressure, high-resolution NMR spectroscopy of proteins, the experimental part deals with instrumentation. The main section of the review is devoted to NMR studies of reversible pressure unfolding of proteins with special emphasis on pressure-assisted cold denaturation and the detection of folding intermediates. Recent studies investigating local perturbations in proteins and the experiments following the effects of point mutations on pressure stability of proteins are also discussed. Ribonuclease A, lysozyme, ubiquitin, apomyoglobin, alpha-lactalbumin and troponin C were the model proteins investigated.

  3. Study of biological fluids by nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Kriat, M.; Vion-Dury, J.; Confort-Gouny, S.; Sciaky, M.; Cozzone, P.J.

    1991-01-01

    The use of nuclear magnetic resonance (NMR) spectroscopy in the study of biofluids is rapidly developing and might soon constitute a new major medical application of this technique which benefits from technological and methodological progress such as higher magnetic fields, new probe design, solvent suppression sequences and advanced data processing routines. In this overview, the clinical and pharmacological impact of this new approach is examined, with emphasis on the NMR spectroscopy of plasma, cerebrospinal fluid and urine. Applications to pharmacokinetics and toxicology are illustrated. Interestingly, a number of biochemical components of fluids which are not usually assayed by conventional biochemical methods are readily detected by NMR spectroscopy which is clearly a new competitive entrant among the techniques used in clinical biology. Its ease-of-use, cost effectiveness and high informational content might turn it into a major diagnostic tool in the years to come [fr

  4. Determining phenols in coal conversion products by nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Kanitskaya, L.V.; Kushnarev, D.F.; Polonov, V.M.; Kalabin, G.A.

    1985-03-01

    Possibility of using nuclear magnetic resonance spectra of the hydrogen 1 (/sup 1/H) isotope for a qualitative and quantitative evaluation of the hydroxyl groups in the products of coal processing is investigated. The basis of the method is the fact that in NMR spectra of the /sup 1/H in organic compounds with acid protons, the latter are unprotected when strong bases are used as solvents because of intermolecular hydrogen bonds. The resin from the medium-temperature semicoking of Cheremkhovskii coals, its hydrogenate, and phenol fraction of the hydrogenate were used for the investigation. The results were compared with the results of other NMR spectroscopy methods. The high solubility of hexamethanol and the fact that the products can be analyzed in the natural state, are some advantages of the method. 18 references.

  5. Solid state nuclear magnetic resonance investigations of advanced energy materials

    Science.gov (United States)

    Bennett, George D.

    In order to better understand the physical electrochemical changes that take place in lithium ion batteries and asymmetric hybrid supercapacitors solid state nuclear magnetic resonance (NMR) spectroscopy has been useful to probe and identify changes on the atomic and molecular level. NMR is used to characterize the local environment and investigate the dynamical properties of materials used in electrochemical storage devices (ESD). NMR investigations was used to better understand the chemical composition of the solid electrolyte interphase which form on the negative and positive electrodes of lithium batteries as well as identify the breakdown products that occur in the operation of the asymmetric hybrid supercapacitors. The use of nano-structured particles in the development of new materials causes changes in the electrical, structural and other material properties. NMR was used to investigate the affects of fluorinated and non fluorinated single wall nanotubes (SWNT). In this thesis three experiments were performed using solid state NMR samples to better characterize them. The electrochemical reactions of a lithium ion battery determine its operational profile. Numerous means have been employed to enhance battery cycle life and operating temperature range. One primary means is the choice and makeup of the electrolyte. This study focuses on the characteristics of the solid electrolyte interphase (SEI) that is formed on the electrodes surface during the charge discharge cycle. The electrolyte in this study was altered with several additives in order to determine the influence of the additives on SEI formation as well as the intercalation and de-intercalation of lithium ions in the electrodes. 7Li NMR studies where used to characterize the SEI and its composition. Solid state NMR studies of the carbon enriched acetonitrile electrolyte in a nonaqueous asymmetric hybrid supercapacitor were performed. Magic angle spinning (MAS) coupled with cross polarization NMR

  6. Nuclear magnetic resonance experiments with dc SQUID amplifiers

    International Nuclear Information System (INIS)

    Heaney, M.B.

    1990-11-01

    The development and fabrication of dc SQUIDs (Superconducting QUantum Interference Devices) with Nb/Al 2 O 3 /Nb Josephson junctions is described. A theory of the dc SQUID as a radio-frequency amplifier is presented, with an optimization strategy that accounts for the loading and noise contributions of the postamplifier and maximizes the signal-to-noise ratio of the total system. The high sensitivity of the dc SQUID is extended to high field NMR. A dc SQUID is used as a tuned radio-frequency amplifier to detect pulsed nuclear magnetic resonance at 32 MHz from a metal film in a 3.5 Tesla static field. A total system noise temperature of 11 K has been achieved, at a bath temperature of 4.2 K. The minimum number of nuclear Bohr magnetons observable from a free precession signal after a single pulse is about 2 x 10 17 in a bandwidth of 25 kHz. In a separate experiment, a dc SQUID is used as a rf amplifier in a NQR experiment to observe a new resonance response mechanism. The net electric polarization of a NaClO 3 crystal due to the precessing electric quadrupole moments of the Cl nuclei is detected at 30 MHz. The sensitivity of NMR and NQR spectrometers using dc SQUID amplifiers is compared to the sensitivity of spectrometers using conventional rf amplifiers. A SQUID-based spectrometer has a voltage sensitivity which is comparable to the best achieved by a FET-based spectrometer, at these temperatures and operating frequencies

  7. A personal computer-based nuclear magnetic resonance spectrometer

    Science.gov (United States)

    Job, Constantin; Pearson, Robert M.; Brown, Michael F.

    1994-11-01

    Nuclear magnetic resonance (NMR) spectroscopy using personal computer-based hardware has the potential of enabling the application of NMR methods to fields where conventional state of the art equipment is either impractical or too costly. With such a strategy for data acquisition and processing, disciplines including civil engineering, agriculture, geology, archaeology, and others have the possibility of utilizing magnetic resonance techniques within the laboratory or conducting applications directly in the field. Another aspect is the possibility of utilizing existing NMR magnets which may be in good condition but unused because of outdated or nonrepairable electronics. Moreover, NMR applications based on personal computer technology may open up teaching possibilities at the college or even secondary school level. The goal of developing such a personal computer (PC)-based NMR standard is facilitated by existing technologies including logic cell arrays, direct digital frequency synthesis, use of PC-based electrical engineering software tools to fabricate electronic circuits, and the use of permanent magnets based on neodymium-iron-boron alloy. Utilizing such an approach, we have been able to place essentially an entire NMR spectrometer console on two printed circuit boards, with the exception of the receiver and radio frequency power amplifier. Future upgrades to include the deuterium lock and the decoupler unit are readily envisioned. The continued development of such PC-based NMR spectrometers is expected to benefit from the fast growing, practical, and low cost personal computer market.

  8. Nuclear quadrupole resonance applied for arsenic oxide study

    International Nuclear Information System (INIS)

    Correia, J.A.S.

    1991-04-01

    The objectives of this study are mounting a pulsed Nuclear Quadrupole Resonance (NQR) building a flow cryostat capable of varying the temperature continuously from 77 K to 340 K and using the spectrometer and the cryostat to study the polycrystalline arsenic oxide. The spin-lattice relaxation time (T 1 ), the spin-spin relaxation time (T 2 ) and the resonance frequency are obtained as a function of temperature. These data are obtained in 77 to 330 K interval. The relaxation times are obtained using the spin echo technique. The spin echo phenomenon is due to refocusing spins, when a 180 0 C pulse is applied after a 90 0 C pulse. The spin-lattice relaxation time is obtained using the plot of echo amplitude versus the repetition time. The spin-spin relaxation time is obtained using the plot of echo amplitude versus the separation between the 90 0 C - 180 0 C pulses. The theory developed by Bayer is used to explain the spin-lattice relaxation time and the frequency temperature dependence. The spin-spin relaxation time is discussed using the Bloch equations. (author)

  9. Narrow nuclear resonance profiling of Al with subnanometric depth resolution

    International Nuclear Information System (INIS)

    Rosa, E.B.O. da; Krug, C.; Stedile, F.C.; Morais, J.; Baumvol, I.J.R.

    2002-01-01

    We report on the use of the narrow and isolated resonance at 404.9 keV in the cross-section curve of the 27 Al(p,γ) 28 Si nuclear reaction for profiling Al in ultrathin aluminum oxide films on Si. The samples were characterized as-deposited and after thermal annealing, so that Al transport could be studied. An estimated depth resolution of approximately 0.4 nm near the surface of the films could be obtained owing to: (i) the very small resonance width; (ii) the high stopping power of Al 2 O 3 for 404.9 keV protons; (iii) the high energy stability of the proton beam provided by the 500 kV HVEE ion implanter at Porto Alegre; and (iv) an apparent thickness magnification by a factor between 2.0 and 2.4 with the use of glancing incidence. This technique is compared to other methods for Al profiling like medium energy ion scattering and some sputtering-based techniques

  10. Nuclear magnetic resonance. Present results and its application to renal pathology. Experimental study of hydronephrosis

    International Nuclear Information System (INIS)

    Bertrand, P.

    1987-01-01

    Results of proton nuclear magnetic resonance imaging and relaxation time measurement of experimental hydronephrosis in mice are presented. The study is preceded by a description of the physical principles underlying the phenomenon of nuclear magnetic resonance and of its biomedical applications and with a review of the clinical use of NMR imaging in renal pathology [fr

  11. Line broadening interference for high-resolution nuclear magnetic resonance spectra under inhomogeneous magnetic fields

    International Nuclear Information System (INIS)

    Wei, Zhiliang; Yang, Jian; Lin, Yanqin; Chen, Zhong; Chen, Youhe

    2015-01-01

    Nuclear magnetic resonance spectroscopy serves as an important tool for analyzing chemicals and biological metabolites. However, its performance is subject to the magnetic-field homogeneity. Under inhomogeneous fields, peaks are broadened to overlap each other, introducing difficulties for assignments. Here, we propose a method termed as line broadening interference (LBI) to provide high-resolution information under inhomogeneous magnetic fields by employing certain gradients in the indirect dimension to interfere the magnetic-field inhomogeneity. The conventional spectral-line broadening is thus interfered to be non-diagonal, avoiding the overlapping among adjacent resonances. Furthermore, an inhomogeneity correction algorithm is developed based on pattern recognition to recover the high-resolution information from LBI spectra. Theoretical deductions are performed to offer systematic and detailed analyses on the proposed method. Moreover, experiments are conducted to prove the feasibility of the proposed method for yielding high-resolution spectra in inhomogeneous magnetic fields

  12. Performance analysis of nuclear materials accounting systems

    International Nuclear Information System (INIS)

    Cobb, D.D.; Shipley, J.P.

    1979-01-01

    Techniques for analyzing the level of performance of nuclear materials accounting systems in terms of the four performance measures, total amount of loss, loss-detection time, loss-detection probability, and false-alarm probability, are presented. These techniques are especially useful for analyzing the expected performance of near-real-time (dynamic) accounting systems. A conservative estimate of system performance is provided by the CUSUM (cumulative summation of materials balances) test. Graphical displays, called performance surfaces, are developed as convenient tools for representing systems performance, and examples from a recent safeguards study of a nuclear fuels reprocessing plant are given. 6 refs

  13. Use of the image by nuclear magnetic resonance (nucleography) in obstetrical aspects. Part 1. Emprego da imagem por ressonancia magnetica nuclear (nucleografia) em obstetricia. Parte 1

    Energy Technology Data Exchange (ETDEWEB)

    Lacreta, O [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina

    1987-09-01

    Nuclear magnetic resonance (nucleography) is a new method to study human body. In this paper the physical principles on nuclear magnetic resonance and its applications to the pregnant women are presented. (author).

  14. Pygmy quadrupole resonance as a manifestation of the nuclear skin

    Energy Technology Data Exchange (ETDEWEB)

    Tsoneva, Nadia [Frankfurt Institute for Advanced Studies (FIAS), 60438 Frankfurt am Main (Germany); Institut fuer Theoretische Physik, Universitaet Giessen (Germany); Lenske, Horst [Institut fuer Theoretische Physik, Universitaet Giessen (Germany)

    2016-07-01

    Recently, a new mode of nuclear excitation called pygmy quadrupole resonance (PQR) was theoretically predicted in the framework of energy-density functional (EDF) theory plus three-phonon quasiparticle-phonon model (QPM) in Sn isotopic chain. It is closely connected with higher order multipole vibrations of nuclear skin induced by the action of the electromagnetic and hadronic external fields. The predictions initiated new experiments using ({sup 17}O,{sup 17}O{sup '}γ), (α,α{sup '}γ) and (γ,γ{sup '}) reactions which were carried out in {sup 124}Sn nucleus. The aim was to probe for the first time experimentally, the possibility of existence of PQR. The detailed analysis of the obtained experimental results in comparison with the EDF+QPM theory indicates clearly the presence of a multitude of discrete low-energy 2{sup +} excitations of neutron type which can be addressed to PQR mode. The independent measurements of B(E2) values with different probes and the theory allow to identify the dominant isoscalar character of these states. Furthermore, newly determined γ-decay branching ratios exclude a statistical origin of the PQR strength. The latter are important to discriminate between PQR and multiphonon excitations.

  15. Nuclear magnetic resonance method and apparatus for reducing motion artifacts

    International Nuclear Information System (INIS)

    Bailes, D.R.

    1988-01-01

    A nuclear magnetic resonance apparatus for imaging a region of a body in which part of the region is moving with a motion such that its displacement with respect to time is a nonmonotonic function during a time period over which a plurality of NMR data signals, which together define an image, are collected. The apparatus is described comprising: excitation means arranged to excite nuclear magnetic spins preferentially in the region; encoding means arranged to encode the magnetic spins; data collection means arranged to collect data signals representative of encoded magnetic spins; display means responsive to collected data signals to display an image of the region; measuring means arranged to produce an output indicative of the displacement of the moving part of the region; and control means for controlling the encoding means during the time period in dependence on the output of the measuring means so that data signals collected during the time period are collected in an order dependent on the motion such that motion artifacts are reduced

  16. Quantitative dosing by nuclear magnetic resonance; Dosages quantitatifs par resonance magnetique nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, I [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The measurement of the absolute concentration of a heavy water reference containing approximately 99.8 per cent of D{sub 2}O has been performed, by an original magnetic resonance method ('Adiabatic fast passage method') with a precision of 5.10{sup -5} on the D{sub 2}O concentration. (author) [French] La determination du titre absolu d'une eau lourde etalon de teneur approximative de 99,8 pour cent de D{sub 2}O a pu etre effectuee par une methode originale de resonance magnetique ('Methode de passage rapide adiabatique') a une precision de 5.10{sup -5} sur le titre de D{sub 2}O. (auteur)

  17. Quantitative dosing by nuclear magnetic resonance; Dosages quantitatifs par resonance magnetique nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, I. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The measurement of the absolute concentration of a heavy water reference containing approximately 99.8 per cent of D{sub 2}O has been performed, by an original magnetic resonance method ('Adiabatic fast passage method') with a precision of 5.10{sup -5} on the D{sub 2}O concentration. (author) [French] La determination du titre absolu d'une eau lourde etalon de teneur approximative de 99,8 pour cent de D{sub 2}O a pu etre effectuee par une methode originale de resonance magnetique ('Methode de passage rapide adiabatique') a une precision de 5.10{sup -5} sur le titre de D{sub 2}O. (auteur)

  18. Proceedings of the nuclear magnetic resonance user meeting. Anais do Encontro de Usuarios de Ressonancia Magnetica Nuclear

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    Studies on utilization of nuclear magnetic resonance, such as: chemical analysis in complexes and organic compounds; structures and magnetic properties of solids; construction of images and; spectrometer designs, are presented. (M.C.K.).

  19. Nuclear fuel elements design, fabrication and performance

    CERN Document Server

    Frost, Brian R T

    1982-01-01

    Nuclear Fuel Elements: Design, Fabrication and Performance is concerned with the design, fabrication, and performance of nuclear fuel elements, with emphasis on fast reactor fuel elements. Topics range from fuel types and the irradiation behavior of fuels to cladding and duct materials, fuel element design and modeling, fuel element performance testing and qualification, and the performance of water reactor fuels. Fast reactor fuel elements, research and test reactor fuel elements, and unconventional fuel elements are also covered. This volume consists of 12 chapters and begins with an overvie

  20. Material degradation of liquid organic semiconductors analyzed by nuclear magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fukushima, Tatsuya; Yamamoto, Junichi; Fukuchi, Masashi; Kaji, Hironori, E-mail: kaji@scl.kyoto-u.ac.jp [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan); Hirata, Shuzo; Jung, Heo Hyo; Adachi, Chihaya [Center for Organic Photonics and Electronics Research (OPERA), Kyusyu University, 744 Motooka, Nishi, Fukuoka 819-0395 (Japan); Hirata, Osamu; Shibano, Yuki [Nissan Chemical Industries, LTD, 722-1 Tsuboi, Funabashi 274-8507 (Japan)

    2015-08-15

    Liquid organic light-emitting diodes (liquid OLEDs) are unique devices consisting only of liquid organic semiconductors in the active layer, and the device performances have been investigated recently. However, the device degradation, especially, the origin has been unknown. In this study, we show that material degradation occurs in liquid OLEDs, whose active layer is composed of carbazole with an ethylene glycol chain. Nuclear magnetic resonance (NMR) experiments clearly exhibit that the dimerization reaction of carbazole moiety occurs in the liquid OLEDs during driving the devices. In contrast, cleavages of the ethylene glycol chain are not detected within experimental error. The dimerization reaction is considered to be related to the device degradation.

  1. Time domain-nuclear magnetic resonance study of chars from southern hardwoods

    International Nuclear Information System (INIS)

    Elder, Thomas; Labbe, Nicole; Harper, David; Rials, Timothy

    2006-01-01

    Chars from the thermal degradation of silver maple (Acer saccharinum), red maple (Acer rubrum), sugar maple (Acer saccharum), and white oak (Quercus spp.), performed at temperatures from 250 to 350 o C, were examined using time domain-nuclear magnetic resonance spectroscopy. Prior to analysis, the chars were equilibrated under conditions insuring the presence of bound water only and both bound water and free water. Transverse relaxation times were found to be related to the moisture content of the chars, which varied with temperature. At elevated temperatures the number of signals assigned to free water decreased, indicative of an increase in pore size within the chars

  2. Nuclear magnetic resonance studies of macroscopic morphology and dynamics

    International Nuclear Information System (INIS)

    Barrall, G.A.; Lawrence Berkeley Lab., CA

    1995-09-01

    Nuclear magnetic resonance techniques are traditionally used to study molecular level structure and dynamics with a noted exception in medically applied NMR imaging (MRI). In this work, new experimental methods and theory are presented relevant to the study of macroscopic morphology and dynamics using NMR field gradient techniques and solid state two-dimensional exchange NMR. The goal in this work is not to take some particular system and study it in great detail, rather it is to show the utility of a number of new and novel techniques using ideal systems primarily as a proof of principle. By taking advantage of the analogy between NMR imaging and diffraction, one may simplify the experiments necessary for characterizing the statistical properties of the sample morphology. For a sample composed of many small features, e.g. a porous medium, the NMR diffraction techniques take advantage of both the narrow spatial range and spatial isotropy of the sample's density autocorrelation function to obtain high resolution structural information in considerably less time than that required by conventional NMR imaging approaches. The time savings of the technique indicates that NMR diffraction is capable of finer spatial resolution than conventional NMR imaging techniques. Radio frequency NMR imaging with a coaxial resonator represents the first use of cylindrically symmetric field gradients in imaging. The apparatus as built has achieved resolution at the micron level for water samples, and has the potential to be very useful in the imaging of circularly symmetric systems. The study of displacement probability densities in flow through a random porous medium has revealed the presence of features related to the interconnectedness of the void volumes. The pulsed gradient techniques used have proven successful at measuring flow properties for time and length scales considerably shorter than those studied by more conventional techniques

  3. SILICON COMPATIBLE ACOUSTIC WAVE RESONATORS: DESIGN, FABRICATION AND PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Aliza Aini Md Ralib

    2014-12-01

    Full Text Available ABSTRACT: Continuous advancement in wireless technology and silicon microfabrication has fueled exciting growth in wireless products. The bulky size of discrete vibrating mechanical devices such as quartz crystals and surface acoustic wave resonators impedes the ultimate miniaturization of single-chip transceivers. Fabrication of acoustic wave resonators on silicon allows complete integration of a resonator with its accompanying circuitry.  Integration leads to enhanced performance, better functionality with reduced cost at large volume production. This paper compiles the state-of-the-art technology of silicon compatible acoustic resonators, which can be integrated with interface circuitry. Typical acoustic wave resonators are surface acoustic wave (SAW and bulk acoustic wave (BAW resonatorsPerformance of the resonator is measured in terms of quality factor, resonance frequency and insertion loss. Selection of appropriate piezoelectric material is significant to ensure sufficient electromechanical coupling coefficient is produced to reduce the insertion loss. The insulating passive SiO2 layer acts as a low loss material and aims to increase the quality factor and temperature stability of the design. The integration technique also is influenced by the fabrication process and packaging.  Packageless structure using AlN as the additional isolation layer is proposed to protect the SAW device from the environment for high reliability. Advancement in miniaturization technology of silicon compatible acoustic wave resonators to realize a single chip transceiver system is still needed. ABSTRAK: Kemajuan yang berterusan dalam teknologi tanpa wayar dan silikon telah menguatkan pertumbuhan yang menarik dalam produk tanpa wayar. Saiz yang besar bagi peralatan mekanikal bergetar seperti kristal kuarza menghalang pengecilan untuk merealisasikan peranti cip. Silikon serasi  gelombang akustik resonator mempunyai potensi yang besar untuk menggantikan unsur

  4. Novel nuclear magnetic resonance techniques for studying biological molecules

    International Nuclear Information System (INIS)

    Laws, David D.

    2000-01-01

    Over the fifty-five year history of Nuclear Magnetic Resonance (NMR), considerable progress has been made in the development of techniques for studying the structure, function, and dynamics of biological molecules. The majority of this research has involved the development of multi-dimensional NMR experiments for studying molecules in solution, although in recent years a number of groups have begun to explore NMR methods for studying biological systems in the solid-state. Despite this new effort, a need still exists for the development of techniques that improve sensitivity, maximize information, and take advantage of all the NMR interactions available in biological molecules. In this dissertation, a variety of novel NMR techniques for studying biomolecules are discussed. A method for determining backbone (φ/ψ) dihedral angles by comparing experimentally determined 13 C a , chemical-shift anisotropies with theoretical calculations is presented, along with a brief description of the theory behind chemical-shift computation in proteins and peptides. The utility of the Spin-Polarization Induced Nuclear Overhauser Effect (SPINOE) to selectively enhance NMR signals in solution is examined in a variety of systems, as are methods for extracting structural information from cross-relaxation rates that can be measured in SPINOE experiments. Techniques for the production of supercritical and liquid laser-polarized xenon are discussed, as well as the prospects for using optically pumped xenon as a polarizing solvent. In addition, a detailed study of the structure of PrP 89-143 is presented. PrP 89-143 is a 54 residue fragment of the prion proteins which, upon mutation and aggregation, can induce prion diseases in transgenic mice. Whereas the structure of the wild-type PrP 89-143 is a generally unstructured mixture of α-helical and β-sheet conformers in the solid state, the aggregates formed from the PrP 89-143 mutants appear to be mostly β-sheet.

  5. Accelerating two-dimensional nuclear magnetic resonance correlation spectroscopy via selective coherence transfer

    Science.gov (United States)

    Ye, Qimiao; Chen, Lin; Qiu, Wenqi; Lin, Liangjie; Sun, Huijun; Cai, Shuhui; Wei, Zhiliang; Chen, Zhong

    2017-01-01

    Nuclear magnetic resonance (NMR) spectroscopy serves as an important tool for both qualitative and quantitative analyses of various systems in chemistry, biology, and medicine. However, applications of one-dimensional 1H NMR are often restrained by the presence of severe overlap among different resonances. The advent of two-dimensional (2D) 1H NMR constitutes a promising alternative by extending the crowded resonances into a plane and thereby alleviating the spectral congestions. However, the enhanced ability in discriminating resonances is achieved at the cost of extended experimental duration due to necessity of various scans with progressive delays to construct the indirect dimension. Therefore, in this study, we propose a selective coherence transfer (SECOT) method to accelerate acquisitions of 2D correlation spectroscopy by converting chemical shifts into spatial positions within the effective sample length and then performing an echo planar spectroscopic imaging module to record the spatial and spectral information, which generates 2D correlation spectrum after 2D Fourier transformation. The feasibility and effectiveness of SECOT have been verified by a set of experiments under both homogeneous and inhomogeneous magnetic fields. Moreover, evaluations of SECOT for quantitative analyses are carried out on samples with a series of different concentrations. Based on these experimental results, the SECOT may open important perspectives for fast, accurate, and stable investigations of various chemical systems both qualitatively and quantitatively.

  6. Method and apparatus for imaging substances in biological samples by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Shaw, D.

    1984-01-01

    A method of determining the distribution of non-proton nuclei having a magnetic moment in a biological sample is described. It comprises subjecting the sample to a magnetic field, irradiating the sample with RF radiation at a proton magnetic resonance frequency and deriving a first NMR signal, indicative of electromagnetic absorption of the sample at the proton magnetic resonance frequency. A second such NMR signal at the proton resonance frequency is then derived from the sample in the presence of RF radiation at the nuclear magnetic resonance frequency of the non-proton nuclei so as to decouple protons in the sample from the non-proton nuclei. By applying an imaging technique, an image indicative of the spatial variation of the difference between the first and second signals can be produced. Imaging may be performed on the difference between the two NMR signals, or on each NMR signal followed by subtraction of the images. The method can be used to trace how a 13 C-labelled material introduced into a patient, and its breakdown products, become distributed. (author)

  7. Bipolar programmable current supply for superconducting nuclear magnetic resonance magnets

    Science.gov (United States)

    Koivuniemi, Jaakko; Luusalo, Reeta; Hakonen, Pertti

    1998-09-01

    In high resolution continuous-wave nuclear magnetic resonance (NMR) work well-reproducible, linear sweeps of current are needed. We have developed a microcontroller based programmable current supply, tested with superconducting magnets with inductance of 10 mH and 10 H. We achieved a resolution and noise of 4 ppm. The supply has an internal sweep with programmable ramping rate and a possibility for remote operation from a computer with either GPIB or RS232 interface. It is based on an 18-bit D/A converter. The maximum output current is ±10 A, the sweep rate can be set between 1 μA/s-140 mA/s, and the maximum output voltage is ±2.5 V. In work at ultralow temperatures, especially in superconducting quantum interference device NMR, all rf interference to the experiment should be avoided. One of the sources of this kind of unwanted input is the digital switching noise of fast logic devices. We discuss this problem in the context of our design.

  8. Discrete decoding based ultrafast multidimensional nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Wei, Zhiliang; Lin, Liangjie; Ye, Qimiao; Li, Jing; Cai, Shuhui; Chen, Zhong

    2015-01-01

    The three-dimensional (3D) nuclear magnetic resonance (NMR) spectroscopy constitutes an important and powerful tool in analyzing chemical and biological systems. However, the abundant 3D information arrives at the expense of long acquisition times lasting hours or even days. Therefore, there has been a continuous interest in developing techniques to accelerate recordings of 3D NMR spectra, among which the ultrafast spatiotemporal encoding technique supplies impressive acquisition speed by compressing a multidimensional spectrum in a single scan. However, it tends to suffer from tradeoffs among spectral widths in different dimensions, which deteriorates in cases of NMR spectroscopy with more dimensions. In this study, the discrete decoding is proposed to liberate the ultrafast technique from tradeoffs among spectral widths in different dimensions by focusing decoding on signal-bearing sites. For verifying its feasibility and effectiveness, we utilized the method to generate two different types of 3D spectra. The proposed method is also applicable to cases with more than three dimensions, which, based on the experimental results, may widen applications of the ultrafast technique

  9. Discrete decoding based ultrafast multidimensional nuclear magnetic resonance spectroscopy

    Science.gov (United States)

    Wei, Zhiliang; Lin, Liangjie; Ye, Qimiao; Li, Jing; Cai, Shuhui; Chen, Zhong

    2015-07-01

    The three-dimensional (3D) nuclear magnetic resonance (NMR) spectroscopy constitutes an important and powerful tool in analyzing chemical and biological systems. However, the abundant 3D information arrives at the expense of long acquisition times lasting hours or even days. Therefore, there has been a continuous interest in developing techniques to accelerate recordings of 3D NMR spectra, among which the ultrafast spatiotemporal encoding technique supplies impressive acquisition speed by compressing a multidimensional spectrum in a single scan. However, it tends to suffer from tradeoffs among spectral widths in different dimensions, which deteriorates in cases of NMR spectroscopy with more dimensions. In this study, the discrete decoding is proposed to liberate the ultrafast technique from tradeoffs among spectral widths in different dimensions by focusing decoding on signal-bearing sites. For verifying its feasibility and effectiveness, we utilized the method to generate two different types of 3D spectra. The proposed method is also applicable to cases with more than three dimensions, which, based on the experimental results, may widen applications of the ultrafast technique.

  10. Characterization of Canadian coals by nuclear magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.; Ripmeester, J.

    1983-06-01

    Apparent aromaticities of a series of Canadian coals of different rank were estimated by solid state nuclear magnetic resonance spectroscopy. The aromaticities varied from 0.57 for a lignite up to 0.86 for a semi-anthracite coal. The aromaticities correlated well with fixed carbon and oxygen content of the coals as well as with the mean reflectance of the coals. Correlations were also established between aromaticities and the H/C and H/SUB/a/SUB/r/SUB/u/C/SUB/a/SUB/r ratios of the coals. Uncertainties in calculation of the hypothetical H/SUB/a/SUB/r/SUB/u/C/SUB/a/SUB/r ratios, from experimental data were pointed out. Structural parameters of the chars derived from the coals by pyrolysis at 535 C were, also, estimated. The H/C and H/SUB/a/SUB/r/SUB/u/C/SUB/a/SUB/r ratios of the chars were markedly lower than those of coals. This was complemented by higher apparent aromaticities of the chars compared with the coals. (21 refs.)

  11. Phosphorus nuclear magnetic resonance imaging in solid bone

    International Nuclear Information System (INIS)

    Li, Limin.

    1990-01-01

    Phosphorus ( 31 P) nuclear magnetic resonance (NMR) double-pulse transient experiments of solid bone have shown that the spins dephased by the dipolar spin-spin interactions can be refocused with a 90 degree-β pulse sequence so that an echo is observable at some time following the second pulse. The decay time constant of the maximum echo amplitude is larger than that of the free induction decay (FID) signal from a single 90 degree pulse. Depending on the nutation angle of the second pulse, the former decay time constant is about three-five times as long as the latter one. The dipolar-echo properties of the bone may be relevant with the interpair dipolar interactions. The experiments have also show that, in general, the time for the transient signal from the double pulses to reach the maximum amplitude is not equal to the pulse separation. This can be attributed to the effect of the heteronuclear dipolar interactions. In addition, it is found experimentally that refocused gradients applied only in a time interval of the formation of an echo have the capability of phase-encoding spatial information. Based on this, a new imaging method was proposed. With the method, several 31 P images of the solid bone samples have been obtained. The picture element size is 1-1.5 mm with very good signal-to-noise ratios. The imaging ability of the refocused gradients may be relevant with the inhomogeneous local field produced by the interpair dipolar interactions

  12. Proton nuclear magnetic resonance studies on brain edema

    International Nuclear Information System (INIS)

    Naruse, S.; Horikawa, Y.; Tanaka, C.; Hirakawa, K.; Nishikawa, H.; Yoshizaki, K.

    1982-01-01

    The water in normal and edematous brain tissues of rats was studied by the pulse nuclear magnetic resonance (NMR) technique, measuring the longitudinal relaxation time (T1) and the transverse relaxation time (T2). In the normal brain, T1 and T2 were single components, both shorter than in pure water. Prolongation and separation of T2 into two components, one fast and one slow, were the characteristic findings in brain edema induced by both cold injury and triethyl tin (TET), although some differences between the two types of edema existed in the content of the lesion and in the degree of changes in T1 and T2 values. Quantitative analysis of T1 and T2 values in their time course relating to water content demonstrated that prolongation of T1 referred to the volume of increased water in tissues examined, and that two phases of T2 reflected the distribution and the content of the edema fluid. From the analysis of the slow component of T2 versus water content during edema formation, it was demonstrated that the increase in edema fluid was steady, and its content was constant during formation of TET-induced edema. On the contrary, during the formation of cold-injury edema, water-rich edema fluid increased during the initial few hours, and protein-rich edema fluid increased thereafter. It was concluded that proton NMR relaxation time measurements may provide new understanding in the field of brain edema research

  13. Two-dimensional nuclear magnetic resonance of quadrupolar systems

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shuanhu [Univ. of California, Berkeley, CA (United States)

    1997-09-01

    This dissertation describes two-dimensional nuclear magnetic resonance theory and experiments which have been developed to study quadruples in the solid state. The technique of multiple-quantum magic-angle spinning (MQMAS) is extensively reviewed and expanded upon in this thesis. Specifically, MQMAS is first compared with another technique, dynamic-angle spinning (DAS). The similarity between the two techniques allows us to extend much of the DAS work to the MQMAS case. Application of MQMAS to a series of aluminum containing materials is then presented. The superior resolution enhancement through MQMAS is exploited to detect the five- and six-coordinated aluminum in many aluminosilicate glasses. Combining the MQMAS method with other experiments, such as HETCOR, greatly expands the possibility of the use of MQMAS to study a large range of problems and is demonstrated in Chapter 5. Finally, the technique switching-angle spinning (SAS) is applied to quadrupolar nuclei to fully characterize a quadrupolar spin system in which all of the 8 NMR parameters are accurately determined. This dissertation is meant to demonstrate that with the combination of two-dimensional NMR concepts and new advanced spinning technologies, a series of multiple-dimensional NMR techniques can be designed to allow a detailed study of quadrupolar nuclei in the solid state.

  14. Nuclear magnetic resonance of randomly diluted magnetic materials

    International Nuclear Information System (INIS)

    Magon, C.J.

    1985-01-01

    The temperature dependence of the nuclear relaxation rates and line shapes of the F O resonance in the diluted antiferromagnet Fe x Zn 1-x F 2 and Mn x Zn 1-x F 2 are studied over a large temperature range T N 1 ) of the F O nuclei, which are not transfer hyperfine coupled to the Fe (or Mn) spins, have been measured and calculated as a function of the concentration x. Good agreement with experiment is found for the theoretical results, which have been obtained in the range 0.1 ≤ x ≤ 0.8. The temperature dependence of 1/T 1 for T N 1 data near T N was used to study Random Field Effects on the critical behavior of Mn .65 Zn . 3 5 F 2 , for fields applied parallel and perpendicular to the easy (C) axis. It was found that the transition temperature T N depressed substantially with field only for H o || C. The experimental results are in general accord with the theory for Random Field Effects in disordered, anisotropic antiferromagnets. The critical divergence of the inhomogeneously broadened F O NMR was studied in Fe .6 Zn .4 F 2 above T N . The experimental results agree with Heller's calculation of the NMR line broadening by Random Field Effects. With H o || C the line shape changes from Gaussian towards Lozentzian for t -2 and below T N its line width increase qualitatively following the increase in the sublattice magnetization. (author)

  15. Nuclear Magnetic Resonance Spectroscopy-Based Identification of Yeast.

    Science.gov (United States)

    Himmelreich, Uwe; Sorrell, Tania C; Daniel, Heide-Marie

    2017-01-01

    Rapid and robust high-throughput identification of environmental, industrial, or clinical yeast isolates is important whenever relatively large numbers of samples need to be processed in a cost-efficient way. Nuclear magnetic resonance (NMR) spectroscopy generates complex data based on metabolite profiles, chemical composition and possibly on medium consumption, which can not only be used for the assessment of metabolic pathways but also for accurate identification of yeast down to the subspecies level. Initial results on NMR based yeast identification where comparable with conventional and DNA-based identification. Potential advantages of NMR spectroscopy in mycological laboratories include not only accurate identification but also the potential of automated sample delivery, automated analysis using computer-based methods, rapid turnaround time, high throughput, and low running costs.We describe here the sample preparation, data acquisition and analysis for NMR-based yeast identification. In addition, a roadmap for the development of classification strategies is given that will result in the acquisition of a database and analysis algorithms for yeast identification in different environments.

  16. Work in progress: nuclear magnetic resonance imaging of the gallbladder

    International Nuclear Information System (INIS)

    Hricak, H.; Filly, R.A.; Margulis, A.R.; Moon, K.L.; Crooks, L.E.; Kaufman, L.

    1983-01-01

    A preliminary study of the relation between food intake and intensity of gallbladder bile on nuclear magnetic resonance (NMR) images was made. Twelve subjects (seven volunteers, five patients) were imaged following a minimum of 14 hours of fasting. Six of seven volunteers were reimaged one hour after stimulation by either a fatty meal or an alcoholic beverage. An additional seven patients were imaged two hours after a hospital breakfast. It was found that concentrated bile emits a high-intensity spin echo signal (SE), while hepatic bile in the gallbladder produces a low-intensity SE signal. Following ingestion of cholecystogogue, dilute hepatic bile settles on top of the concentrated bile, each emitting SE signals of different intensity. The average T1 value of concentrated bile was 594 msec, while the T1 vaue of dilute hepatic bile was 2,646 msec. The average T2 values were 104 msec for concentrated bile and 126 msec for dilute bile. The most likely cause for the different SE intensities of bile is the higher water content, and therefore longer T1 or T2 relaxation times, of hepatic bile. It is suggested that NMR imaging has the ability to provide physiological information about the gallbladder and that it may prove to be a simple and safe clinical test of gallbladder function

  17. Nuclear Magnetic Resonance Imaging of Li-ion Battery

    Directory of Open Access Journals (Sweden)

    D. Ohno

    2010-12-01

    Full Text Available Nuclear magnetic resonance (NMR imaging has high sensitivity to proton (1H and lithium (7Li. It is a useful measurement for electrolyte in Li-ion battery. 1H NMR images of lithium ion battery which is composed of LiMn2O4 / LiClO4 + propylene carbonate (PC / Li-metal have been studied. 1H NMR images of electrolyte near cathode material (LiMn2O4 showed anomalous intensity distribution, which was quite inhomogeneous. From NMR images as a function of repetition time (TR, it was concluded that the anomalous intensity distribution was not due to change of relaxation time but an indirect (spatial para-magnetization effect from cathode material. The paramagnetization induced by high magnetic field distorts linearity of magnetic gradient field, leading to apparent intensity variance. This functional image is an easy diagnostic measurement for magnetization of cathode material, which allows the possibility to check uniformity of cathode material and change of magnetization under electrochemical process.

  18. Multinuclear nuclear magnetic resonance spectroscopic study of cartilage proteoglycans

    Energy Technology Data Exchange (ETDEWEB)

    Lerner, L.

    1985-01-01

    Hyaline cartilage is a composite material whose major function is to withstand compression while retaining flexibility. Its mechanical properties are affected by tissue hydration and ionic composition. Models of the mechanical behavior of cartilage have incorporated certain assumptions about the interactions of the major components of cartilage: collagen, proteoglycans, water, and cations. To determine the validity of these assumption, the authors have used nuclear magnetic resonance spectroscopy (NMR). Two approaches have been used: (a) natural abundance carbon-13 NMR; and (b) NMR of sodium-23, potassium-39, magnesium-25, and calcium-43. Evidence from studies in intact tissues are reinforced by extensive measurements on solutions of proteoglycans and other relevant macromolecules. Based on the measurements of NMR relaxation rates and lineshapes reported here, it is concluded that neither sodium nor potassium interact strongly with bovine nasal proteoglycan aggregates or their substituent glycosaminoglycan chains in solution. Proteoglycans do bind magnesium and calcium. Therefore there is a qualitative difference between monovalent and divalent cations, which is not taken into account by polyelectrolyte models or models for the ionic dependence of mechanical properties. Cation binding to heparin, which has a higher charge density than cartilage proteoglycans, was also studied. The results presented here establish that heparin binds sodium, magnesium, and calcium.

  19. Nuclear resonance fluorescence of {sup 203,205}Tl

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, Fabian; Fritzsche, Matthias; Pietralla, Norbert; Savran, Deniz; Weller, Henry; Zweidinger, Markus [Institut fuer Kernphysik, Technische Universitaet, Darmstadt (Germany); Rusev, Gencho; Tonchev, Anton P.; Tornow, Werner [Triangle Universities Nuclear Laboratory, Duke University, Durham (United States); Zilges, Andreas [Institut fuer Kernphysik, Universitaet Koeln (Germany)

    2009-07-01

    In order to investigate the dipole strength distribution in Thalium isotopes we have studied Nuclear Resonance Fluorescence of a sample composed of natural Thallium (consisting of 30% {sup 203}Tl and 70% {sup 205}Tl). Unpolarized bremsstrahlung with photo energies up to 7.5 MeV was used at the High Intensity Photon Setup (HIPS) at S-DALINAC at the IKP Darmstadt. 24 fluorescent {gamma}-ray transitions were observed, 19 of them for the first time. For the assignment of the polarity of two prominent {gamma}-ray transitions, one at 4.7 MeV and one at 4.9 MeV, the polarized photon beam of the High Intensity {gamma}-ray Source (HI{gamma}S) at Duke University was used. The experiment at HI{gamma}S revealed the existence of a photo-excited state of {sup 205}Tl at an excitation energy of 4.971 MeV that exhibits a transition to the first excited state at 203 keV.

  20. Gradient coil system for nuclear magnetic resonance apparatus

    International Nuclear Information System (INIS)

    Frese, G.; Siebold, H.

    1984-01-01

    A gradient coil system for an image-generating, nuclear magnetic resonance tomographic apparatus, particularly a zeugmatographic apparatus. The gradient coil system is arranged on a support body of rotational symmetry, illustratively a hollow cylindrical support body, having an axis which extends along the z-direction of an x, y, z coordinate system which has an origin in the center of imaging region. The gradient coil system contains two pairs of toroidal individual coils which are arranged symmetrically with respect to an x-y plane which extends through the center of the imaging region and which are arranged perpendicular to the z-axis. The direction of current flow in the individual coils of a coil pair is opposite to the direction of flow in the individual coils of the other coil pair. Moreover, further sets of coils are provided for generating field gradient Gx in the x-direction, and Gy in the y-direction. The hollow cylindrical shape of the support body on which the individual coils are arranged permit an imaging region having a substantially spherical volume with a substantially constant field gradient Gz to be achieved. Each of the coils has a predetermined linkage factor which corresponds to the product of the current flowing through the number of coil turns of the coil. Those coils which are arranged further from the plane of symmetry have a substantially larger linkage factor than the coils which are nearer to the plane of symmetry

  1. Nuclear Magnetic Resonance: new applications in the quantification and assessment of polysaccharide-based vaccine intermediates

    International Nuclear Information System (INIS)

    Garrido, Raine; Velez, Herman; Verez, Vicente

    2013-01-01

    Nuclear Magnetic Resonance has become the choice for structural studies, identity assays and simultaneous quantification of active pharmaceutical ingredient of different polysaccharide-based vaccine. In the last two decades, the application of quantitative Nuclear Magnetic Resonance had an increasing impact to support several quantification necessities. The technique involves experiments with several modified parameters in order to obtain spectra with quantifiable signals. The present review is supported by some recent relevant reports and it discusses several applications of NMR in carbohydrate-based vaccines. Moreover, it emphasizes and describes several parameters and applications of quantitative Nuclear Magnetic Resonance

  2. Methodology for nuclear magnetic resonance and ion cyclotron resonance mass spectrometry

    International Nuclear Information System (INIS)

    Sehgal, Akansha

    2014-01-01

    This thesis encompasses methodological developments in both nuclear magnetic resonance and Fourier transform ion cyclotron resonance mass spectrometry. The NMR section explores the effects of scalar relaxation on a coupled nucleus to measure fast exchange rates. In order to quantify these rates accurately, a precise knowledge of the chemical shifts of the labile protons and of the scalar couplings is normally required. We applied the method to histidine where no such information was available a priori, neither about the proton chemical shifts nor about the one-bond scalar coupling constants J( 1 H 15 N), since the protons were invisible due to fast exchange. We have measured the exchange rates of the protons of the imidazole ring and of amino protons in histidine by indirect detection via 15 N. Not only the exchange rate constants, but also the elusive chemical shifts of the protons and the coupling constants could be determined. For the mass spectrometry section, the ion isolation project was initiated to study the effect of phase change of radiofrequency pulses. Excitation of ions in the ICR cell is a linear process, so that the pulse voltage required for ejecting ions must be inversely proportional to the pulse duration. A continuous sweep pulse propels the ion to a higher radius, whereas a phase reversal causes the ion to come to the centre. This represents the principle of 'notch ejection', wherein the ion for which the phase is reversed is retained in the ICR cell, while the remaining ions are ejected. The manuscript also contains a theoretical chapter, wherein the ion trajectories are plotted by solving the Lorentzian equation for the three-pulse scheme used for two-dimensional ICR. Through our simulations we mapped the ion trajectories for different pulse durations and for different phase relations. (author)

  3. The effects of proton-beam quality on the production of gamma rays for nuclear resonance absorption in nitrogen

    International Nuclear Information System (INIS)

    Graybill, R.; Morgado, R.E.; Cappiello, C.C.

    1994-05-01

    The authors describe a method for performing nuclear-resonance absorption with the proton beam from a radio-frequency quadrupole (RFQ) linear accelerator. The objective was to assess the suitability of the pulsed beam from an RFQ to image nitrogen compared to electrostatic accelerators. This choice of accelerator results in trade-offs in performance and complexity, in return for the prospect of higher average current. In spite of a reduced resonance attenuation coefficient in nitrogen, they successfully produced three-dimensional tomographic images of real explosives in luggage the first time the unoptimized system was operated. The results and assessments of the initial laboratory measurements are reported

  4. The effects of proton-beam quality on the production of gamma rays for nuclear resonance absorption in nitrogen

    Energy Technology Data Exchange (ETDEWEB)

    Graybill, R. [ed.; Morgado, R.E.; Cappiello, C.C. [and others

    1994-05-01

    The authors describe a method for performing nuclear-resonance absorption with the proton beam from a radio-frequency quadrupole (RFQ) linear accelerator. The objective was to assess the suitability of the pulsed beam from an RFQ to image nitrogen compared to electrostatic accelerators. This choice of accelerator results in trade-offs in performance and complexity, in return for the prospect of higher average current. In spite of a reduced resonance attenuation coefficient in nitrogen, they successfully produced three-dimensional tomographic images of real explosives in luggage the first time the unoptimized system was operated. The results and assessments of the initial laboratory measurements are reported.

  5. The SNS Resonance Control Cooling System Control Valve Upgrade Performance

    International Nuclear Information System (INIS)

    Williams, Derrick C.; Schubert, James Phillip; Tang, Johnny Y.

    2008-01-01

    The normal-conducting linac of the Spallation Neutron Source (SNS) uses 10 separate Resonance Control Cooling System (RCCS) water skids to control the resonance of 6 Drift Tube Linac (DTL) and 4 Coupled Cavity Linac (CCL) accelerating structures. The RCCS water skids use 2 control valves; one to regulate the chilled water flow and the other to bypass water to a chilled water heat exchanger. These valves have hydraulic actuators that provide position and feedback to the control system. Frequency oscillations occur using these hydraulic actuators due to their coarse movement and control of the valves. New pneumatic actuator and control positioners have been installed on the DTL3 RCCS water skid to give finer control and regulation of DTL3 cavity temperature. This paper shows a comparison of resonance control performance for the two valve configurations.

  6. Nuclear isovector giant resonances excited by pion single charge exchange

    International Nuclear Information System (INIS)

    King, B.H.

    1993-07-01

    This thesis is an experimental study of isovector giant resonances in light nuclei excited by pion single charge exchange reactions. Giant dipole resonances in light nuclei are known to be highly structured. For the mass 9 and 13 giant dipole resonances, isospin considerations were found to be very important to understanding this structure. by comparing the excitation functions from cross section measurements of the (π + , π 0 ) and (π, π 0 ) inclusive reactions, the authors determined the dominant isospin structure of the analog IVGR's. The comparison was made after decomposing the cross section into resonant and non-resonant components. This decomposition is made in the framework of strong absorption and quasi-free scattering. Measurements in the region of the isovector giant dipole resonances (IVGDR) were made to cover the inclusive angular distributions out to the second minimum. Study of the giant resonance decay process provides further understanding of the resonances. This study was carried out by observing the (π + , π 0 p) coincident reactions involving the resonances of 9 B and 13 N excited from 9 Be and 13 C nuclei. These measurements determined the spectra of the decay protons. This method also permitted a decomposition of the giant resonances into their isospin components. The multipolarities of the resonances were revealed by the decay proton angular correlations which, for dipoles, are of the form 1 + A 2 P 2 (cos θ)

  7. Significantly improving nuclear resonance fluorescence non-destructive assay by using the integral resonance transmission method and photofission

    International Nuclear Information System (INIS)

    Angell, Christopher T.; Hayakawa, Takehito; Shizuma, Toshiyuki; Hajima, Ryoichi

    2013-01-01

    Non-destructive assay (NDA) of 239 Pu in spent nuclear fuel or melted fuel using a γ-ray beam is possible using self absorption and the integral resonance transmission method. The method uses nuclear resonance absorption where resonances in 239 Pu remove photons from the beam, and the selective absorption is detected by measuring the decrease in scattering in a witness target placed in the beam after the fuel, consisting of the isotope of interest, namely 239 Pu. The method is isotope specific, and can use photofission or scattered γ-rays to assay the 239 Pu. It overcomes several problems related to NDA of melted fuel, including the radioactivity of the fuel, and the unknown composition and geometry. This talk will explain the general method, and how photofission can be used to assay specific isotopes, and present example calculations. (author)

  8. Performing a nuclear facility EMI audit

    International Nuclear Information System (INIS)

    White, D.R.J.

    1993-01-01

    This paper addresses several questions which may arise when performing a nuclear facility EMI audit. Among the issues addressed are how a nuclear electrical power plant can ensure that it has taken adequate EMC measures to protect it from hostile electromagnetic ambient environments, means by which these measures can be implemented with sufficient integrity and reliability, and how often an inspection or audit should be performed to assess the EMC measures. Means of assessing EMI hardening and effective control of aging effects are also discussed. 2 figs

  9. Contribution to the study of nuclear resonance in magnetic media (1963)

    International Nuclear Information System (INIS)

    Hartmann-Boutron, F.

    1963-06-01

    An attempt is made to interpret the results of nuclear magnetic resonance experiments made by various workers on ferro and ferrimagnetic compounds of the iron group. The problems encountered are the following: effects of the dipolar fields and the hyperfine structure anisotropy; signal intensity; frequency pulling due to the Suhl-Nakamura interaction between nuclear spins ; nuclear relaxation and ferrimagnetic resonance in single domain samples of impure YIG; nuclear relaxation in the Bloch walls of insulators. The results of our calculations are generally in good agreement with experiment. (author) [fr

  10. Nuclear magnetic resonance data of C36H30Br2OSb2

    Science.gov (United States)

    Mikhova, B. M.

    This document is part of Part 6 `Organic Metalloid Compounds' of Subvolume D 'Chemical Shifts and Coupling Constants for Carbon-13' of Landolt-Börnstein III/35 'Nuclear Magnetic Resonance Data', Group III 'Condensed Matter'.

  11. Nuclear magnetic resonance data of C36H30Cl2OSb2

    Science.gov (United States)

    Mikhova, B. M.

    This document is part of Part 6 `Organic Metalloid Compounds' of Subvolume D 'Chemical Shifts and Coupling Constants for Carbon-13' of Landolt-Börnstein III/35 'Nuclear Magnetic Resonance Data', Group III 'Condensed Matter'.

  12. Statistical uncertainties of nondestructive assay for spent nuclear fuel by using nuclear resonance fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Shizuma, Toshiyuki, E-mail: shizuma.toshiyuki@jaea.go.jp [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Hayakawa, Takehito; Angell, Christopher T.; Hajima, Ryoichi [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Minato, Futoshi; Suyama, Kenya [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Seya, Michio [Integrated Support Center for Nuclear Nonproliferation and Nuclear Security, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1198 (Japan); Johnson, Micah S. [Lawrence Livermore National Laboratory, 7000 East Ave. Livermore, CA 94550 (United States); Department of Physics and Astronomy, San Jose State University, One Washington Square, San Jose, CA 9519 (United States); McNabb, Dennis P. [Lawrence Livermore National Laboratory, 7000 East Ave. Livermore, CA 94550 (United States)

    2014-02-11

    We estimated statistical uncertainties of a nondestructive assay system using nuclear resonance fluorescence (NRF) for spent nuclear fuel including low-concentrations of actinide nuclei with an intense, mono-energetic photon beam. Background counts from radioactive materials inside the spent fuel were calculated with the ORIGEN2.2-UPJ burn-up computer code. Coherent scattering contribution associated with Rayleigh, nuclear Thomson, and Delbrück scattering was also considered. The energy of the coherent scattering overlaps with that of NRF transitions to the ground state. Here, we propose to measure NRF transitions to the first excited state to avoid the coherent scattering contribution. Assuming that the total NRF cross-sections are in the range of 3–100 eV b at excitation energies of 2.25, 3.5, and 5 MeV, statistical uncertainties of the NRF measurement were estimated. We concluded that it is possible to assay 1% actinide content in the spent fuel with 2.2–3.2% statistical precision during 4000 s measurement time for the total integrated cross-section of 30 eV b at excitation energies of 3.5–5 MeV by using a photon beam with an intensity of 10{sup 6} photons/s/eV. We also examined both the experimental and theoretical NRF cross-sections for actinide nuclei. The calculation based on the quasi-particle random phase approximation suggests the existence of strong magnetic dipole resonances at excitation energies ranging from 2 to 6 MeV with the scattering cross-sections of tens eV b around 5 MeV in {sup 238}U.

  13. Novel nuclear magnetic resonance techniques for studying biological molecules

    Energy Technology Data Exchange (ETDEWEB)

    Laws, David Douglas [Univ. of California, Berkeley, CA (United States)

    2000-06-01

    Over the fifty-five year history of Nuclear Magnetic Resonance (NMR), considerable progress has been made in the development of techniques for studying the structure, function, and dynamics of biological molecules. The majority of this research has involved the development of multi-dimensional NMR experiments for studying molecules in solution, although in recent years a number of groups have begun to explore NMR methods for studying biological systems in the solid-state. Despite this new effort, a need still exists for the development of techniques that improve sensitivity, maximize information, and take advantage of all the NMR interactions available in biological molecules. In this dissertation, a variety of novel NMR techniques for studying biomolecules are discussed. A method for determining backbone (Φ/Ψ) dihedral angles by comparing experimentally determined 13Ca, chemical-shift anisotropies with theoretical calculations is presented, along with a brief description of the theory behind chemical-shift computation in proteins and peptides. The utility of the Spin-Polarization Induced Nuclear Overhauser Effect (SPINOE) to selectively enhance NMR signals in solution is examined in a variety of systems, as are methods for extracting structural information from cross-relaxation rates that can be measured in SPINOE experiments. Techniques for the production of supercritical and liquid laser-polarized xenon are discussed, as well as the prospects for using optically pumped xenon as a polarizing solvent. In addition, a detailed study of the structure of PrP 89-143 is presented. PrP 89-143 is a 54 residue fragment of the prion proteins which, upon mutation and aggregation, can induce prion diseases in transgenic mice. Whereas the structure of the wild-type PrP 89-143 is a generally unstructured mixture of α-helical and β-sheet conformers in the solid state, the aggregates formed from the PrP 89-143 mutants appear to be mostly β-sheet.

  14. Science and history explored by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Baias, Maria Antoaneta

    2009-01-01

    Nuclear Magnetic Resonance was chosen as the main tool for investigating different biological and chemical systems, as it is unique in providing the information details about the morphology and molecular structures and conformations by which the fundamental properties of these biological and chemical systems can be understood. Proton spin-diffusion experiments combined with 13 C CPMAS spectroscopy were successfully applied to characterize the changes that occur during the thermal denaturation of keratin fibers from wool and hair. A model describing both the effect of thermal denaturation and the effect of different chemical treatments on keratin fibers is presented. Proton NMR spectroscopy was used for studying the proton exchange in Sulfonated Polyether Ether Ketone proton exchange membranes revealing that the water exchange processes in hydrated SPEEK-silica membranes are more efficient when low concentrations of polyethoxysiloxane (PEOS) are used for the membrane preparation. Proton 1D exchange spectroscopy combined with transverse relaxation measurements offered good insight in the state of water in hydrated SPEEK/SiO 2 membranes revealing that concentrations of 5%-10% wt. PEOS could enhance the electrical conductivity of PEM. Hyperpolarized 129 Xe NMR spectroscopy was successfully applied for monitoring the free radical polymerization reactions of methyl methacrylate, methyl acrylate and the copolymerization of methyl methacrylate and methyl acrylate. The observation of Xe chemical shift and linewidths during the reactions reveal information about the polymer chain growths during the polymerizations. The successful application of the NMR-MOUSE to visualise the different anatomical layers with varying proton densities opens the possibility of its use in clinical studies such as osteoporosis for bone density measurements. The NMR-MOUSE was also successfully applied for the analysis of violins and bows and a classification of the violins and bows as a function of

  15. Unconventional Tight Reservoirs Characterization with Nuclear Magnetic Resonance

    Science.gov (United States)

    Santiago, C. J. S.; Solatpour, R.; Kantzas, A.

    2017-12-01

    The increase in tight reservoir exploitation projects causes producing many papers each year on new, modern, and modified methods and techniques on estimating characteristics of these reservoirs. The most ambiguous of all basic reservoir property estimations deals with permeability. One of the logging methods that is advertised to predict permeability but is always met by skepticism is Nuclear Magnetic Resonance (NMR). The ability of NMR to differentiate between bound and movable fluids and providing porosity increased the capability of NMR as a permeability prediction technique. This leads to a multitude of publications and the motivation of a review paper on this subject by Babadagli et al. (2002). The first part of this presentation is dedicated to an extensive review of the existing correlation models for NMR based estimates of tight reservoir permeability to update this topic. On the second part, the collected literature information is used to analyze new experimental data. The data are collected from tight reservoirs from Canada, the Middle East, and China. A case study is created to apply NMR measurement in the prediction of reservoir characterization parameters such as porosity, permeability, cut-offs, irreducible saturations etc. Moreover, permeability correlations are utilized to predict permeability. NMR experiments were conducted on water saturated cores. NMR T2 relaxation times were measured. NMR porosity, the geometric mean relaxation time (T2gm), Irreducible Bulk Volume (BVI), and Movable Bulk Volume (BVM) were calculated. The correlation coefficients were computed based on multiple regression analysis. Results are cross plots of NMR permeability versus the independently measured Klinkenberg corrected permeability. More complicated equations are discussed. Error analysis of models is presented and compared. This presentation is beneficial in understanding existing tight reservoir permeability models. The results can be used as a guide for choosing

  16. Resolution Improvement in Multidimensional Nuclear Magnetic Resonance Spectroscopy of Proteins

    International Nuclear Information System (INIS)

    Duma, L.

    2004-01-01

    The work presented in this thesis is concerned with both liquid-state and solid-state nuclear magnetic resonance (NMR) spectroscopy. Most of this work is devoted to the investigation by solid-state NMR of C 13 -enriched compounds with the principal aim of presenting techniques devised for further improving the spectral resolution in multidimensional NMR of microcrystalline proteins. In fully C 13 -labelled compounds, the J-coupling induces a broadening of the carbon lineshapes. We show that spin-state-selective technique called IPAP can be successfully combined with standard polarisation transfer schemes in order to remove the J-broadening in multidimensional solid-state NMR correlation experiments of fully C 13 -enriched proteins. We present subsequently two techniques tailored for liquid-state NMR spectroscopy. The carbon directly detected techniques provide chemical shift information for all backbone hetero-nuclei. They are very attracting for the study of large bio-molecular systems or for the investigation of paramagnetic proteins. In the last part of this thesis, we study the spin-echo J-modulation for homonuclear two-spin 1/2 systems. Under magic-angle spinning, the theory of J-induced spin-echo modulation allows to derive a set of modulation regimes which give a spin-echo modulation exactly equal to the J-coupling. We show that the chemical-shift anisotropy and the dipolar interaction tend to stabilize the spin-echo J-modulation. The theoretical conclusions are supported by numerical simulations and experimental results obtained for three representative samples containing C 13 spin pairs. (author)

  17. Neutron Resonance Theory for Nuclear Reactor Applications: Modern Theory and Practices.

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Richard N. [Argonne National Lab. (ANL), Argonne, IL (United States); Blomquist, Roger N. [Argonne National Lab. (ANL), Argonne, IL (United States); Leal, Luiz C. [Inst. de Radioprotection et de Sûrete Nucleaire (ISRN), Fontenay-aux-Roses (France); Yang, Won Sik [Purdue Univ., West Lafayette, IN (United States)

    2016-09-24

    The neutron resonance phenomena constitute one of the most fundamental subjects in nuclear physics as well as in reactor physics. It is the area where the concepts of nuclear interaction and the treatment of the neutronic balance in reactor fuel lattices become intertwined. The latter requires the detailed knowledge of resonance structures of many nuclides of practical interest to the development of nuclear energy. The most essential element in reactor physics is to provide an accurate account of the intricate balance between the neutrons produced by the fission process and neutrons lost due to the absorption process as well as those leaking out of the reactor system. The presence of resonance structures in many major nuclides obviously plays an important role in such processes. There has been a great deal of theoretical and practical interest in resonance reactions since Fermi’s discovery of resonance absorption of neutrons as they were slowed down in water. The resonance absorption became the center of attention when the question was raised as to the feasibility of the self-sustaining chain reaction in a natural uranium-fueled system. The threshold of the nuclear era was crossed almost eighty years ago when Fermi and Szilard observed that a substantial reduction in resonance absorption is possible if the uranium was made into the form of lumps instead of a homogeneous mixture with water. In the West, the first practical method for estimating the resonance escape probability in a reactor cell was pioneered by Wigner et al in early forties.

  18. High performance structural ceramics for nuclear industry

    International Nuclear Information System (INIS)

    Pujari, Vimal K.; Faker, Paul

    2006-01-01

    A family of Saint-Gobain structural ceramic materials and products produced by its High performance Refractory Division is described. Over the last fifty years or so, Saint-Gobain has been a leader in developing non oxide ceramic based novel materials, processes and products for application in Nuclear, Chemical, Automotive, Defense and Mining industries

  19. Magnetic resonance imaging of the wrist: Diagnostic performance statistics

    International Nuclear Information System (INIS)

    Hobby, Jonathan L.; Tom, Brian D.M.; Bearcroft, Philip W.P.; Dixon, Adrian K.

    2001-01-01

    AIM: To review the published diagnostic performance statistics for magnetic resonance imaging (MRI) of the wrist for tears of the triangular fibrocartilage complex, the intrinsic carpal ligaments, and for osteonecrosis of the carpal bones. MATERIALS AND METHODS: We used Medline and Embase to search the English language literature. Studies evaluating the diagnostic performance of MRI of the wrist in living patients with surgical confirmation of MR findings were identified. RESULTS: We identified 11 studies reporting the diagnostic performance of MRI for tears of the triangular fibrocartilage complex for a total of 410 patients, six studies for the scapho-lunate ligament (159 patients), six studies for the luno-triquetral ligament (142 patients) and four studies (56 patients) for osteonecrosis of the carpal bones. CONCLUSIONS: Magnetic resonance imaging is an accurate means of diagnosing tears of the triangular fibrocartilage and carpal osteonecrosis. Although MRI is highly specific for tears of the intrinsic carpal ligaments, its sensitivity is low. The diagnostic performance of MRI in the wrist is improved by using high-resolution T2* weighted 3D gradient echo sequences. Using current imaging techniques without intra-articular contrast medium, magnetic resonance imaging cannot reliably exclude tears of the intrinsic carpal ligaments. Hobby, J.L. (2001)

  20. Nuclear power plant performance. Status and trends

    International Nuclear Information System (INIS)

    Glorian, D.

    1995-01-01

    The performance of nuclear power plants can be assessed in several different fields: operating costs, safety, reliability of electricity generation, impact on the environment and personnel protection (industrial safety, radiation protection, etc.). Comparing national and international performance levels involves the use of performance indicators, together with a terminology, precise definitions and computerized data collection and processing facilities. The paper gives a brief review of the different actions undertaken during the last ten years to achieve international harmonization in the use of indicators. The main international indicators in use today by virtually all nuclear operators around the world are examined. Figures are given for each of these main indicators. In particularly, the levels of 'excellence' achieved throughout the world are discussed, together with the difficulties encountered in trying to match them or indeed maintain them. Future prospects regarding both the efforts made towards achieving international harmonization and the optimum use of this system of international performance indicators are examined, in order to achieve mutual enhancement through this approach to feedback of experience. Considering the overall performance indicators in use, it must be clearly recognized that, over the last ten years, the nuclear industry has made a tremendous effort to improve performance; the challenge for the future is to maintain a very high level of quality in the area of safety by keeping the operating costs (and investment costs for future plants) within a reasonable range

  1. Investigations into the adsorption behaviour of zeolites using nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Hennig, H.J.

    1973-01-01

    The interactions between adsorbed molecules and the walls of the cavities in faujasite have been investigated; even the sodium form of the A type zeolite was included in the investigation. The nuclear magnetic resonance measurements were performed with a varian DP-60 wide line resonance spectrometer. The measuring frequency was generally 16 MHg the modulation frequency 20 Hz. The resonance effect was recorded in the form of the derived absorption signal. It was found that the water molecules form hydrogen bonds to the oxygen ions of the alumozilicate structure, the hydrogen sulphide on the other hand splits off protons which under formation of OH groups bind in the oxygen ions of the alumosilicate structure. The results obtained with sulphur dioxide imply that these molecules bind onto the oxygen ions of the alumosilicate structure via sulphur and thus occupy their free electron pairs. The translation mobility of the absorbed molecules present at room temperature is very much reduced when cooling down to certain temperatures; this solidification temperature of the adsorbate lies below that of the pure liquids. Probably the absorbed molecules are deposited in one or several layers onto the walls of the cavity. Prefered sorption sites for the faujasites are the sodium ions in front of the six-membered rings on the walls fo the large cavities, with NaA, on the other hand, the sodium ions are in the eight-membered rings. (ORU) [de

  2. A deuterium and carbon nuclear magnetic resonance spectroscopic investigation of blood flow and carbohydrate metabolism

    International Nuclear Information System (INIS)

    Bosch, C.S.E.

    1988-01-01

    The purpose of this study is the development and application of nuclear magnetic resonance (NMR) spectroscopic techniques for this study of whole tissue metabolism, tissue perfusion and blood flow. The feasibility of spin imaging deuterium-enriched tissue water is demonstrated in cat brain in vivo and in situ. The potential application of D 2 O administration to deuterium-flow-imaging is considered. NMR investigations of hepatic carbohydrate metabolism were performed in rat liver in vivo and in situ. A coaxial, double-surface-coil, double-resonance probe was developed for carbon detection while decoupling neighboring proton scalar interactions ( 13 C-[ 1 H]) in hepatic tissue within the living animal. Hormonal and substrate regulation of hepatic glucose and glycogen metabolism was investigated by monitoring the metabolic fate of an administered c-dose of [1- 13 C]glucose. Label flux was directed primarily into newly-synthesized 13 C-labeled glycogen. A multiple resonance ( 1 H, 13 C, 31 P) liver perfusion probe was designed for complimentary carbohydrate metabolic studies in rat liver in vitro. A description of the 13 C-[ 1 H]/ 31 P NMR perfusion probe is given. The surgical technique used for liver excision and peripheral life-support apparatus required to maintain hepatic function are also detailed

  3. Multi-dimensional Inversion Modeling of Surface Nuclear Magnetic Resonance (SNMR Data for Groundwater Exploration

    Directory of Open Access Journals (Sweden)

    Warsa

    2014-07-01

    Full Text Available Groundwater is an important economic source of water supply for drinking water and irrigation water for agriculture. Surface nuclear magnetic resonance (SNMR sounding is a relatively new geophysical method that can be used to determine the presence of culturally and economically important substances, such as subsurface water or hydrocarbon distribution. SNMR sounding allows the determination of water content and pore size distribution directly from the surface. The SNMR method is performed by stimulating an alternating current pulse through an antenna at the surface in order to confirm the existence of water in the subsurface. This paper reports the development of a 3-D forward modeling code for SNMR amplitudes and decay times, after which an improved 2-D and 3-D inversion algorithm is investigated, consisting of schemes for regularizing model parameterization. After briefly reviewing inversion schemes generally used in geophysics, the special properties of SNMR or magnetic resonance sounding (MRS inversion are evaluated. We present an extension of MRS to magnetic resonance tomography (MRT, i.e. an extension for 2-D and 3-D investigation, and the appropriate inversions.

  4. Monitoring of the insecticide trichlorfon by phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy

    International Nuclear Information System (INIS)

    Talebpour, Zahra; Ghassempour, Alireza; Zendehzaban, Mehdi; Bijanzadeh, Hamid Reza; Mirjalili, Mohammad Hossein

    2006-01-01

    Trichlorfon is an organophosphorus insecticide, which is extensively being used for protection of fruit crops. Trichlorfon is a thermal labile compound, which cannot be easily determined by gas chromatography (GC) and has no suitable group for sensitive detection by high performance liquid chromatography (HPLC). In this study, a 31 P nuclear magnetic resonance ( 31 P NMR) has been described for monitoring of trichlorfon without any separation step. The quantitative works of 31 P NMR spectroscopy has been performed in the presence of an internal standard (hexamethylphosphoramide). Limit of detection (LOD) for this method has been found to be 55 mg L -1 , without any sample preparation, and the linear working range was 150-5500 mg L -1 . Relative standard deviation (R.S.D.%) of the method for three replicates within and between days was obtained ≤9%. The average recovery efficiency was approximately 99-112%. This method was applied for monitoring trichlorfon in a commercial insecticide sample and tomato sample

  5. Water in Brain Edema : Observations by the Pulsed Nuclear Magnetic Resonance Technique

    NARCIS (Netherlands)

    GO, KG; Edzes, HT

    The state of water in three types of brain edema and in normal brain of the rat was studied by the pulsed nuclear magnetic resonance (NMR) technique. In cold-induced edema and in osmotic edema both in cortex and in white matter, the water protons have longer nuclear magnetic relaxation times than in

  6. Performance Criteria of Nuclear Space Propulsion Systems

    Science.gov (United States)

    Shepherd, L. R.

    Future exploration of the solar system on a major scale will require propulsion systems capable of performance far greater than is achievable with the present generation of rocket engines using chemical propellants. Viable missions going deeper into interstellar space will be even more demanding. Propulsion systems based on nuclear energy sources, fission or (eventually) fusion offer the best prospect for meeting the requirements. The most obvious gain coming from the application of nuclear reactions is the possibility, at least in principle, of obtaining specific impulses a thousandfold greater than can be achieved in chemically energised rockets. However, practical considerations preclude the possibility of exploiting the full potential of nuclear energy sources in any engines conceivable in terms of presently known technology. Achievable propulsive power is a particularly limiting factor, since this determines the acceleration that may be obtained. Conventional chemical rocket engines have specific propulsive powers (power per unit engine mass) in the order of gigawatts per tonne. One cannot envisage the possibility of approaching such a level of performance by orders of magnitude in presently conceivable nuclear propulsive systems. The time taken, under power, to reach a given terminal velocity is proportional to the square of the engine's exhaust velocity and the inverse of its specific power. An assessment of various nuclear propulsion concepts suggests that, even with the most optimistic assumptions, it could take many hundreds of years to attain the velocities necessary to reach the nearest stars. Exploration within a range of the order of a thousand AU, however, would appear to offer viable prospects, even with the low levels of specific power of presently conceivable nuclear engines.

  7. Nuclear Magnetic Resonance (NMR) Spectroscopic Characterization of Nanomaterials and Biopolymers

    Science.gov (United States)

    Guo, Chengchen

    Nanomaterials have attracted considerable attention in recent research due to their wide applications in various fields such as material science, physical science, electrical engineering, and biomedical engineering. Researchers have developed many methods for synthesizing different types of nanostructures and have further applied them in various applications. However, in many cases, a molecular level understanding of nanoparticles and their associated surface chemistry is lacking investigation. Understanding the surface chemistry of nanomaterials is of great significance for obtaining a better understanding of the properties and functions of the nanomaterials. Nuclear magnetic resonance (NMR) spectroscopy can provide a familiar means of looking at the molecular structure of molecules bound to surfaces of nanomaterials as well as a method to determine the size of nanoparticles in solution. Here, a combination of NMR spectroscopic techniques including one- and two-dimensional NMR spectroscopies was used to investigate the surface chemistry and physical properties of some common nanomaterials, including for example, thiol-protected gold nanostructures and biomolecule-capped silica nanoparticles. Silk is a natural protein fiber that features unique properties such as excellent mechanical properties, biocompatibility, and non-linear optical properties. These appealing physical properties originate from the silk structure, and therefore, the structural analysis of silk is of great importance for revealing the mystery of these impressive properties and developing novel silk-based biomaterials as well. Here, solid-state NMR spectroscopy was used to elucidate the secondary structure of silk proteins in N. clavipes spider dragline silk and B. mori silkworm silk. It is found that the Gly-Gly-X (X=Leu, Tyr, Gln) motif in spider dragline silk is not in a beta-sheet or alpha-helix structure and is very likely to be present in a disordered structure with evidence for 31-helix

  8. Nuclear power performance and safety. V.5. Nuclear fuel cycle

    International Nuclear Information System (INIS)

    1988-01-01

    The International Conference on Nuclear Power Performance and Safety, organized by the International Atomic Energy Agency, was held at the Austria Centre Vienna (ACV) in Vienna, Austria, from 28 September to 2 October 1987. The objective of the Conference was to promote an exchange of worldwide information on the current trends in the performance and safety of nuclear power and its fuel cycle, and to take a forward look at the expectations and objectives for the 1990s. Policy decisions for waste management have already been taken in many countries and the 1990s should be a period of demonstration and implementation of these policies. As ilustrated by data presented from a number of countries, many years of experience in radioactive waste management have been achieved and the technology exists to implement the national plans and policies that have been developed. The establishment of criteria, the development of safety performance methodology and site investigation work are key activities essential to the successful selection, characterization and construction of geological repositories for the final disposal of radioactive waste. Considerable work has been done in these areas over the last ten years and will continue into the 1990s. However, countries that are considering geological disposal for high level waste now recognize the need for relating the technical aspects to public understanding and acceptance of the concept and decision making activities. The real challenge for the 1990s in waste disposal will be successfully to integrate technological activities within a process which responds to institutional and public concern. Volume 5 of the Proceedings comprehends the contributions on waste management in the 1990s. Decontamination and decommissioning, waste management, treatment and disposal, nuclear fuel cycle - present and future. Enrichment services and advanced reactor fuels, improvements in reactor fuel utilization and performance, spent fuel management

  9. Operating performance of LWR nuclear generating units

    International Nuclear Information System (INIS)

    Pia, S.

    1984-01-01

    This work aims at reviewing, on the basis of historical data, the operational problem areas which explain the degree of availability and productivity achieved up to now by nuclear power plants in commercial operation in the world. The operating performance data of nuclear power plants area analysed with respect to plant type, size and other significant reference parameters and they are evaluated also by comparison with fossil generating unit data. Major performance indices data are presented for both nuclear and fossil units type and distribution of outage causes. Unplanned full outages caused by nuclear power plant equipment and components failure are particulary emphasized. The trend for unplanned full outages due to the failure of components shows decreasing numerical values in 1981 with respect to the previous years. But this result should be weighed with the increasing plant unavailability hours needed for maintenance and repair action (chiefly preventive maintenance on critical components). This means that the number and downtime of forced outage must be drastically reduced for economic reasons (production losses and problems associated with the unavailable unit unplanned replacement) as well as for plant safe and reliable operation (sudden unavailability of key components and frequency of transients associated with plant shutdown and routine startup operation)

  10. The influence of temperature in the characterization of nuclear resonance

    International Nuclear Information System (INIS)

    Campos, T.P.R. de; Martinez, A.S.

    1986-01-01

    A detailed analysis carried out to determine the temperature effects on the selection of different types of resonance for Resonance Integral calculations is presented. The type of approximation (WR, IR or NR) to be applied to the slowing down integral of the neutron balance equation depends on the relationship between the average energy lost by the neutron and the practical width. A method to include the temperature dependence in the ratio ΔE/GAMMA sub(p) is proposed. The results allowed us to show that this dependence negligence may lead to large errors in the Resonance Integral calculation. (Author) [pt

  11. Nuclear magnetic resonance of laser-polarized noble gases in molecules, materials and organisms

    International Nuclear Information System (INIS)

    Goodson, Boyd M.

    1999-01-01

    Conventional nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI) are fundamentally challenged by the insensitivity that stems from the ordinarily low spin polarization achievable in even the strongest NMR magnets. However, by transferring angular momentum from laser light to electronic and nuclear spins, optical pumping methods can increase the nuclear spin polarization of noble gases by several orders of magnitude, thereby greatly enhancing their NMR sensitivity. This dissertation is primarily concerned with the principles and practice of optically pumped nuclear magnetic resonance (OPNMR). The enormous sensitivity enhancement afforded by optical pumping noble gases can be exploited to permit a variety of novel NMR experiments across many disciplines. Many such experiments are reviewed, including the void-space imaging of organisms and materials, NMR and MRI of living tissues, probing structure and dynamics of molecules in solution and on surfaces, and zero-field NMR and MRI

  12. Nuclear magnetic resonance of laser-polarized noble gases in molecules, materials and organisms

    Energy Technology Data Exchange (ETDEWEB)

    Goodson, Boyd McLean [Univ. of California, Berkeley, CA (United States)

    1999-12-01

    Conventional nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI) are fundamentally challenged by the insensitivity that stems from the ordinarily low spin polarization achievable in even the strongest NMR magnets. However, by transferring angular momentum from laser light to electronic and nuclear spins, optical pumping methods can increase the nuclear spin polarization of noble gases by several orders of magnitude, thereby greatly enhancing their NMR sensitivity. This dissertation is primarily concerned with the principles and practice of optically pumped nuclear magnetic resonance (OPNMR). The enormous sensitivity enhancement afforded by optical pumping noble gases can be exploited to permit a variety of novel NMR experiments across many disciplines. Many such experiments are reviewed, including the void-space imaging of organisms and materials, NMR and MRI of living tissues, probing structure and dynamics of molecules in solution and on surfaces, and zero-field NMR and MRI.

  13. Nuclear Resonance Fluorescence to Measure Plutonium Mass in Spent Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Ludewigt, Bernhard A; Quiter, Brian J.; Ambers, Scott D.

    2011-01-14

    The Next Generation Safeguard Initiative (NGSI) of the U.S Department of Energy is supporting a multi-lab/university collaboration to quantify the plutonium (Pu) mass in spent nuclear fuel (SNF) assemblies and to detect the diversion of pins with non-destructive assay (NDA) methods. The following 14 NDA techniques are being studied: Delayed Neutrons, Differential Die-Away, Differential Die-Away Self-Interrogation, Lead Slowing Down Spectrometer, Neutron Multiplicity, Passive Neutron Albedo Reactivity, Total Neutron (Gross Neutron), X-Ray Fluorescence, {sup 252}Cf Interrogation with Prompt Neutron Detection, Delayed Gamma, Nuclear Resonance Fluorescence, Passive Prompt Gamma, Self-integration Neutron Resonance Densitometry, and Neutron Resonance Transmission Analysis. Understanding and maturity of the techniques vary greatly, ranging from decades old, well-understood methods to new approaches. Nuclear Resonance Fluorescence (NRF) is a technique that had not previously been studied for SNF assay or similar applications. Since NRF generates isotope-specific signals, the promise and appeal of the technique lies in its potential to directly measure the amount of a specific isotope in an SNF assay target. The objectives of this study were to design and model suitable NRF measurement methods, to quantify capabilities and corresponding instrumentation requirements, and to evaluate prospects and the potential of NRF for SNF assay. The main challenge of the technique is to achieve the sensitivity and precision, i.e., to accumulate sufficient counting statistics, required for quantifying the mass of Pu isotopes in SNF assemblies. Systematic errors, considered a lesser problem for a direct measurement and only briefly discussed in this report, need to be evaluated for specific instrument designs in the future. Also, since the technical capability of using NRF to measure Pu in SNF has not been established, this report does not directly address issues such as cost, size

  14. Direct vs statistical decay of nuclear giant multipole resonances

    International Nuclear Information System (INIS)

    Dias, H.; Hussein, M.S.; Carlson, B.V.; Merchant, A.C.; Adhikari, S.K.

    1986-01-01

    A theoretical framework for the description of the decay of giant multipole resonances id developed. Besides the direct decay, both the pre-equilibrium and statistical (compound) decays are taken into account in a consistent way. It is shown that the statistical decay of the giant resonance is not necessarily described by the Hauser-Feshbach theory owing to the presence of a mixing parameter, which measures the degree of fragmentation. Applications are made to several cases. (Author) [pt

  15. Prospects for sub-micron solid state nuclear magnetic resonance imaging with low-temperature dynamic nuclear polarization.

    Science.gov (United States)

    Thurber, Kent R; Tycko, Robert

    2010-06-14

    We evaluate the feasibility of (1)H nuclear magnetic resonance (NMR) imaging with sub-micron voxel dimensions using a combination of low temperatures and dynamic nuclear polarization (DNP). Experiments are performed on nitroxide-doped glycerol-water at 9.4 T and temperatures below 40 K, using a 30 mW tunable microwave source for DNP. With DNP at 7 K, a 0.5 microL sample yields a (1)H NMR signal-to-noise ratio of 770 in two scans with pulsed spin-lock detection and after 80 db signal attenuation. With reasonable extrapolations, we infer that (1)H NMR signals from 1 microm(3) voxel volumes should be readily detectable, and voxels as small as 0.03 microm(3) may eventually be detectable. Through homonuclear decoupling with a frequency-switched Lee-Goldburg spin echo technique, we obtain 830 Hz (1)H NMR linewidths at low temperatures, implying that pulsed field gradients equal to 0.4 G/d or less would be required during spatial encoding dimensions of an imaging sequence, where d is the resolution in each dimension.

  16. Radioimmunotherapy of human lymphoma in athymic, nude mice as monitored by 31P nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Adams, D.A.; DeNardo, G.L.; DeNardo, S.J.; Matson, G.B.; Epstein, A.L.; Bradbury, E.M.

    1985-01-01

    Human B cell lymphoma (Raji) growing in athymic, nude mice has been successfully treated with a single pulse dose of 131 I-labeled monoclonal antibody (Lym-1) specific for this tumor. Sequential in vivo measurements of phosphate metabolites in the tumors by 31 P surface coil nuclear magnetic resonance showed a significant initial decrease of phosphocreatine following radioimmunotherapy. Diminution of relative ATP to Pi peak area ratio suggesting tissue damage occurred within 3-4 days. The sequence of alterations of nuclear magnetic resonance spectra from tumors of treated mice were strikingly different from sequential nuclear magnetic resonance spectra obtained from tumors of control mice. These observations lead us to conclude that 31 P surface coil nuclear magnetic resonance is a promising non-invasive method for assessing and predicting the efficacy of radioimmunotherapy. Further spatial discrimination of the region of tissue observed by the surface coil nuclear magnetic resonance experiment is under exploration in an effort to increase the utility of these methods

  17. Material degradation of liquid organic semiconductors analyzed by nuclear magnetic resonance spectroscopy

    Directory of Open Access Journals (Sweden)

    Tatsuya Fukushima

    2015-08-01

    Full Text Available Liquid organic light-emitting diodes (liquid OLEDs are unique devices consisting only of liquid organic semiconductors in the active layer, and the device performances have been investigated recently. However, the device degradation, especially, the origin has been unknown. In this study, we show that material degradation occurs in liquid OLEDs, whose active layer is composed of carbazole with an ethylene glycol chain. Nuclear magnetic resonance (NMR experiments clearly exhibit that the dimerization reaction of carbazole moiety occurs in the liquid OLEDs during driving the devices. In contrast, cleavages of the ethylene glycol chain are not detected within experimental error. The dimerization reaction is considered to be related to the device degradation.

  18. Nuclear effects in electron spin resonance of crystalline solids

    International Nuclear Information System (INIS)

    Ursu, I.; Nistor, S.V.

    1976-01-01

    A survey on the theory of paramagnetic ions in crystals is given. Some recent applications in which nuclear properties are studied by means of the ESR method are presented against this background. Finer effects in the hyperfine structure of ESR spectra, temperature dependance of the hyperfine coupling of S-state ions, observation of nuclear isotopic shift in ESR represent the applications discussed

  19. Development of 119Sn nuclear resonance scattering of synchrotron radiation and first applications

    International Nuclear Information System (INIS)

    Barla, A.

    2001-01-01

    In the framework of this thesis the NRS technique has been developed and applied, for the first time at the European Synchrotron Radiation Facility, at the resonance of 119 Sn. Elastic nuclear forward scattering (NFS) is ideal for studies of hyperfine interactions, where information about the electronic and magnetic properties of solids is obtained. On the other hand nuclear inelastic scattering (NIS) allows one to study the phonon density of states (DOS) of Moessbauer isotopes in various kinds of systems. In the first stage, technical developments have been made, particularly with regards the used optical elements. A key point has been the construction of a high resolution monochromator (HRM) for the resonance of 119 Sn, with an energy resolution of about 0.65 meV, perfectly suited to perform NIS experiments. A second HRM optimised in throughput has been constructed and used, in combination with focussing elements (bent crystals and compound refractive lenses), to perform NFS experiments at very high pressure. For the first applications of 119 Sn NIS, the phonon DOS of β-Sn has been directly determined from the NIS spectra measured at T = 100 K and T = 300 K. An excellent agreement has been found with the phonon DOS obtained theoretically by previous calculations. Moreover, dynamical and thermodynamical properties of β-Sn extracted from the determined DOS, such as the Lamb-Moessbauer factor and the specific heat, are found to be in good agreement with previously published results. As a first application of 119 Sn NFS experiments at high pressure, the system U(In 1-x Sn x ) 3 has been chosen. (orig.)

  20. Development of {sup 119}Sn nuclear resonance scattering of synchrotron radiation and first applications

    Energy Technology Data Exchange (ETDEWEB)

    Barla, A.

    2001-07-01

    In the framework of this thesis the NRS technique has been developed and applied, for the first time at the European Synchrotron Radiation Facility, at the resonance of {sup 119}Sn. Elastic nuclear forward scattering (NFS) is ideal for studies of hyperfine interactions, where information about the electronic and magnetic properties of solids is obtained. On the other hand nuclear inelastic scattering (NIS) allows one to study the phonon density of states (DOS) of Moessbauer isotopes in various kinds of systems. In the first stage, technical developments have been made, particularly with regards the used optical elements. A key point has been the construction of a high resolution monochromator (HRM) for the resonance of {sup 119}Sn, with an energy resolution of about 0.65 meV, perfectly suited to perform NIS experiments. A second HRM optimised in throughput has been constructed and used, in combination with focussing elements (bent crystals and compound refractive lenses), to perform NFS experiments at very high pressure. For the first applications of {sup 119}Sn NIS, the phonon DOS of {beta}-Sn has been directly determined from the NIS spectra measured at T = 100 K and T = 300 K. An excellent agreement has been found with the phonon DOS obtained theoretically by previous calculations. Moreover, dynamical and thermodynamical properties of {beta}-Sn extracted from the determined DOS, such as the Lamb-Moessbauer factor and the specific heat, are found to be in good agreement with previously published results. As a first application of {sup 119}Sn NFS experiments at high pressure, the system U(In{sub 1-x}Sn{sub x}){sub 3} has been chosen. (orig.)

  1. Coulomb and nuclear excitations of narrow resonances in 17Ne

    Directory of Open Access Journals (Sweden)

    J. Marganiec

    2016-08-01

    Full Text Available New experimental data for dissociation of relativistic 17Ne projectiles incident on targets of lead, carbon, and polyethylene targets at GSI are presented. Special attention is paid to the excitation and decay of narrow resonant states in 17Ne. Distributions of internal energy in the O15+p+p three-body system have been determined together with angular and partial-energy correlations between the decay products in different energy regions. The analysis was done using existing experimental data on 17Ne and its mirror nucleus 17N. The isobaric multiplet mass equation is used for assignment of observed resonances and their spins and parities. A combination of data from the heavy and light targets yielded cross sections and transition probabilities for the Coulomb excitations of the narrow resonant states. The resulting transition probabilities provide information relevant for a better understanding of the 17Ne structure.

  2. Some human performance paradoxes of nuclear operations

    International Nuclear Information System (INIS)

    Otway, H.J.; Misenta, R.

    1980-01-01

    Roughly once a year, an abnormal situation with emergency potential may suddenly break the calm monotony of nuclear-power plant operation. The operating crew, perhaps under-stimulated by monitoring largely automatic processes, may then be expected to make correct inferences and decisions about complex phenomena. However, under stress, the operators may resort to using their 'best-learned responses', inappropriate to the real situation. Recent events at Three Mile Island prompted a variety of suggestions intended to improve operator performance, eg higher qualifications, more pay, or enhanced status. The authors stress the paradoxes of nuclear operation, conclude that some 'intuitively obvious' suggestions might have the opposite effect to that intended, and explore the possibility of introducing frequent, realistic emergency drills. Even this approach raises paradoxes - perhaps the role of the operator should be eliminated, or redefined to allow less human intervention in emergencies. (author)

  3. Nuclear magnetic resonance of D(-)-{alpha}-amino-benzyl penicillin; Ressonancia magnetica nuclear da D(-)-{alpha}-amino-benzil penicilina

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Monica R.M.P.; Gemal, Andre L.; San Gil, Rosane A.S. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Quimica; Menezes, Sonia M.C. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    1995-12-31

    The development of new drugs from penicillins has induced the study of this substances by nuclear magnetic resonance. Several samples of D(-)-{alpha}-amino-benzyl penicillin were analysed using {sup 13} C NMR techniques in aqueous solution and solid state. Spectral data of this compounds were shown and the results were presented and analysed 7 figs., 4 tabs.

  4. 41 Polish Seminar on Nuclear Magnetic Resonance and Its Applications - Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    The Report consist of abstracts of 63 communications presented during the 41 Polish Seminar on Nuclear Magnetic Resonance and Its Applications, held on December 1-2, 2008 in Cracow. Presentations cover a variety of research fields, including magnetic resonance imaging in vivo, applications of NMR spectroscopy to medical diagnosis, studies on molecular properties of different materials as well as quantum chemical calculations of NMR parameters.

  5. Materials of the 39 Polish Seminar on Nuclear Magnetic Resonance and Its Applications - Abstracts

    International Nuclear Information System (INIS)

    2006-01-01

    The Report comprises abstracts of 78 communications presented during the 39 Polish Seminar on Nuclear Magnetic Resonance and Its Applications, held on November, 30 - December, 2006 in Cracow (PL). They cover a variety of research fields, including magnetic resonance imaging in vivo, applications of NMR spectroscopy to medical diagnosis, studies on molecular properties of different materials as well as quantum chemical calculations of NMR parameters

  6. 41 Polish Seminar on Nuclear Magnetic Resonance and Its Applications - Abstracts

    International Nuclear Information System (INIS)

    2008-01-01

    The Report consist of abstracts of 63 communications presented during the 41 Polish Seminar on Nuclear Magnetic Resonance and Its Applications, held on December 1-2, 2008 in Cracow. Presentations cover a variety of research fields, including magnetic resonance imaging in vivo, applications of NMR spectroscopy to medical diagnosis, studies on molecular properties of different materials as well as quantum chemical calculations of NMR parameters

  7. Dynamics of solid alanine by means of nuclear magnetic resonance relaxometry

    Science.gov (United States)

    Kubica-Misztal, A.; Rochowski, P.; Florek-Wojciechowska, M.; Kruk, D.

    2017-04-01

    1H nuclear magnetic resonance relaxometry was applied to investigate the dynamics of l-alanine in the solid phase (powder). The experimental studies were carried out in a very broad frequency range, covering four orders of magnitude—from 4 kHz to 40 MHz (referring to the 1H resonance frequency) in order to probe motional processes of much different time scales by a single experiment. To get access to the dynamics of different proton groups of alanine, the 1H spin-lattice relaxation measurements were performed for non-deuterated and partially deuterated alanine. The experiments were carried out in the temperature range of 293 K-370 K (non-deuterated alanine) and 318 K-370 K (partially deuterated alanine). As a result of a thorough theoretical analysis of the extensive set of experimental results, three motional processes occurring on different time scales are identified and quantitatively described. The slowest process occurs on a time scale of μs and it is attributed to the collective dynamics of a 3D hydrogen bond network of alanine, while the intermediate, attributed to the dynamics of the NH3 group, corresponds to the range of tenths of ns. The fast process describes the rotation of the CH3 group.

  8. The Trojan Horse method for nuclear astrophysics: Recent results on resonance reactions

    Energy Technology Data Exchange (ETDEWEB)

    Cognata, M. La; Pizzone, R. G. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania (Italy); Spitaleri, C.; Cherubini, S.; Romano, S. [Dipartimento di Fisica e Astronomia, Università di Catania, Catania, Italy and Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania (Italy); Gulino, M.; Tumino, A. [Kore University, Enna, Italy and Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania (Italy); Lamia, L. [Dipartimento di Fisica e Astronomia, Università di Catania, Catania (Italy)

    2014-05-09

    Nuclear astrophysics aims to measure nuclear-reaction cross sections of astrophysical interest to be included into models to study stellar evolution and nucleosynthesis. Low energies, < 1 MeV or even < 10 keV, are requested for this is the window where these processes are more effective. Two effects have prevented to achieve a satisfactory knowledge of the relevant nuclear processes, namely, the Coulomb barrier exponentially suppressing the cross section and the presence of atomic electrons. These difficulties have triggered theoretical and experimental investigations to extend our knowledge down to astrophysical energies. For instance, indirect techniques such as the Trojan Horse Method have been devised yielding new cutting-edge results. In particular, I will focus on the application of this indirect method to resonance reactions. Resonances might dramatically enhance the astrophysical S(E)-factor so, when they occur right at astrophysical energies, their measurement is crucial to pin down the astrophysical scenario. Unknown or unpredicted resonances might introduce large systematic errors in nucleosynthesis models. These considerations apply to low-energy resonances and to sub-threshold resonances as well, as they may produce sizable modifications of the S-factor due to, for instance, destructive interference with another resonance.

  9. The Trojan Horse method for nuclear astrophysics: Recent results on resonance reactions

    International Nuclear Information System (INIS)

    Cognata, M. La; Pizzone, R. G.; Spitaleri, C.; Cherubini, S.; Romano, S.; Gulino, M.; Tumino, A.; Lamia, L.

    2014-01-01

    Nuclear astrophysics aims to measure nuclear-reaction cross sections of astrophysical interest to be included into models to study stellar evolution and nucleosynthesis. Low energies, < 1 MeV or even < 10 keV, are requested for this is the window where these processes are more effective. Two effects have prevented to achieve a satisfactory knowledge of the relevant nuclear processes, namely, the Coulomb barrier exponentially suppressing the cross section and the presence of atomic electrons. These difficulties have triggered theoretical and experimental investigations to extend our knowledge down to astrophysical energies. For instance, indirect techniques such as the Trojan Horse Method have been devised yielding new cutting-edge results. In particular, I will focus on the application of this indirect method to resonance reactions. Resonances might dramatically enhance the astrophysical S(E)-factor so, when they occur right at astrophysical energies, their measurement is crucial to pin down the astrophysical scenario. Unknown or unpredicted resonances might introduce large systematic errors in nucleosynthesis models. These considerations apply to low-energy resonances and to sub-threshold resonances as well, as they may produce sizable modifications of the S-factor due to, for instance, destructive interference with another resonance

  10. Reactor shutdown: nuclear power plant performance

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    The article essentially looks at the performance of nine of Sweden's nuclear reactors. A table lists the percentage of time for the first three quarters of 1981 that the reactors were operating, and the number of hours out of service for planned or other reasons. In particular, one station - Ringhals 3 - was out of action because of a damaged tube in the associated steam generator. The same fault occurred with another reactor - Ringhals 4 - before this was brought into service. The reasons for the failure and its importance are briefly discussed. (G.P.)

  11. Proceedings of the 9. Meeting of the nuclear magnetic resonance users. Abstracts

    International Nuclear Information System (INIS)

    2003-01-01

    Nuclear magnetic resonance spectroscopy has been one of the methods more powerful for characterizing and identifying substances, because it allows a detailed evaluation on internal molecular dynamics as well as clarifying its molecular and electronic structures. This meeting has presented a widespread variety of NMR techniques, as well as, advances in the use of this techniques in studies of the structure of liquids and solids. Theoretical and experimental papers are presented, covering the following subjects: nuclear magnetic resonance, structural chemical analysis, chemical shift and NMR spectrometers

  12. Nuclear magnetic resonance imaging in patients with hypertrophic and dilated cardiomyopathy

    International Nuclear Information System (INIS)

    Boisvieux, A.

    1987-01-01

    Patients with hypertrophic and dilated cardiomyopathy and normal subjects were investigated with nuclear magnetic resonance imaging. To evaluate the NMR scanner possibilities, the results were compared with the echocardiographic investigation of the same patients. The capabilities of NMR imaging to provide information about intracardiac anatomy are emphasized. This study is preceded by a description of the physical principles underlying the phenomenon of nuclear magnetic resonance and of the techniques used to obtain NMR images and a review of the clinical use of NMR imaging for cardiac diagnosis [fr

  13. Nuclear-excited Feshbach resonances in the electron scattering from hydrogen halides

    International Nuclear Information System (INIS)

    Knoth, G.; Gote, M.; Radle, M.; Jung, K.; Ehrhardt, H.

    1989-01-01

    The energy dependences of the differential cross sections for the electron impact excitation of the higher vibrational levels (v=2 and v=3) of HF and HCl have been measured. Besides the threshold peak a resonance structure has been observed in the v=3 excitation functions of HF below the cusp structure at the opening of the v=4 channel. This resonance structure is the first experimental proof for the existence of the nuclear-excited Feshbach resonances which are interpreted to be the origin of the threshold peaks in the vibrational excitation channels

  14. Educational simulator app and web page for exploring Nuclear and Compass Magnetic Resonance

    DEFF Research Database (Denmark)

    Hanson, Lars G.

    experimentation that improves understanding of basic MR phenomena. The simulator is used to introduce and explore electromagnetism, magnetic dipoles, static and radiofrequency fields, Compass MR, the free induction decay (FID), relaxation, the Fourier transform (FFT), the resonance condition, spin, precession......, the Larmor equation, Nuclear MR, resonant excitation (linear and quadrature), and off-resonance effects. Methods and implementation: The simulator is a complete HTML5/JavaScript[1,2] rewrite of the JavaCompass[3] so it now executes in modern browsers with no additional software needed. Spin dynamics...

  15. Self consistent and covariant propagation of pions, nucleon and isobar resonances in cold nuclear matter

    International Nuclear Information System (INIS)

    Korpa, C.L.; Lutz, M.F.M.; Technische Univ. Darmstadt

    2003-06-01

    We evaluate the in-medium spectral functions for pions, nucleon and isobar resonances in a self consistent and covariant manner. The calculations are based on a recently developed formulation which leads to predictions in terms of the pion-nucleon scattering phase shifts and a set of Migdal parameters describing important short range correlation effects. We do not observe any significant softening of pion modes if we insist on reasonable isobar resonance properties but predict a considerable broadening of the N(1440) and N(1520) resonances in nuclear matter. (orig.)

  16. Photon nuclear scattering on lead and bismuth in the region of the giant resonance

    International Nuclear Information System (INIS)

    Tamas, Gabriel.

    1976-01-01

    The results of monochromatic photon nuclear scattering studies on natural lead and bismuth targets are presented. The cross sections for the inelastic scattering leading to the first excited levels of 204 Pb, 206 Pb and 207 Pb are important, in agreement with theoretical predictions. The elastic scattering amplitude is related to the total photon absorption by dispersion relations. It is then possible to determine the spin of resonances excited by the reaction studied. Precise measurements carried out between 14 and 20MeV revealed that the angular distribution cannot be explained by a single dipolar resonance. A quadrupolar resonance at E 2 =14MeV must be introduced [fr

  17. Discriminating poststroke depression from stroke by nuclear magnetic resonance spectroscopy-based metabonomic analysis

    Directory of Open Access Journals (Sweden)

    Xiao J

    2016-08-01

    Full Text Available Jianqi Xiao,1,* Jie Zhang,2,* Dan Sun,3,* Lin Wang,4,* Lijun Yu,5 Hongjing Wu,5 Dan Wang,5 Xuerong Qiu5 1Department of Neurosurgery, The First Hospital of Qiqihar City, Qiqihar, 2Department of Internal Medicine, Central Hospital of Jiamusi City, Jiamusi, 3Department of Geriatrics, General Hospital of Daqing Oil Field, Daqing, 4Department of Nursing, 5Department of Neurology, The First Hospital of Qiqihar City, Qiqihar, Heilongjiang, People’s Republic of China *These authors contributed equally to this work Abstract: Poststroke depression (PSD, the most common psychiatric disease that stroke survivors face, is estimated to affect ~30% of poststroke patients. However, there are still no objective methods to diagnose PSD. In this study, to explore the differential metabolites in the urine of PSD subjects and to identify a potential biomarker panel for PSD diagnosis, the nuclear magnetic resonance-based metabonomic method was applied. Ten differential metabolites responsible for discriminating PSD subjects from healthy control (HC and stroke subjects were found, and five of these metabolites were identified as potential biomarkers (lactate, α-hydroxybutyrate, phenylalanine, formate, and arabinitol. The panel consisting of these five metabolites provided excellent performance in discriminating PSD subjects from HC and stroke subjects, achieving an area under the receiver operating characteristic curve of 0.946 in the training set (43 HC, 45 stroke, and 62 PSD subjects. Moreover, this panel could classify the blinded samples from the test set (31 HC, 33 stroke, and 32 PSD subjects with an area under the curve of 0.946. These results laid a foundation for the future development of urine-based objective methods for PSD diagnosis and investigation of PSD pathogenesis. Keywords: poststroke depression, PSD, stroke, nuclear magnetic resonance, NMR, metabonomic

  18. Chiral NNLOsat descriptions of nuclear multipole resonances within the random-phase approximation

    Science.gov (United States)

    Wu, Q.; Hu, B. S.; Xu, F. R.; Ma, Y. Z.; Dai, S. J.; Sun, Z. H.; Jansen, G. R.

    2018-05-01

    We study nuclear multipole resonances in the framework of the random-phase approximation by using the chiral potential NNLOsat. This potential includes two- and three-body terms that have been simultaneously optimized to low-energy nucleon-nucleon scattering data and selected nuclear structure data. Our main focuses have been the isoscalar monopole, isovector dipole, and isoscalar quadrupole resonances of the closed-shell nuclei, 4He, O 16 ,22 ,24 , and Ca,4840. These resonance modes have been widely observed in experiment. In addition, we use a renormalized chiral potential Vlow-k, based on the N3LO two-body potential by Entem and Machleidt [Phys. Rev. C 68, 041001 (2011), 10.1103/PhysRevC.68.041001]. This introduces a dependency on the cutoff parameter used in the normalization procedure as reported in previous works by other groups. While NNLOsat can reasonably reproduce observed multipole resonances, it is not possible to find a single cutoff parameter for the Vlow-k potential that simultaneously describes the different types of resonance modes. The sensitivity to the cutoff parameter can be explained by missing induced three-body forces in the calculations. Our results for neutron-rich O,2422 show a mixing nature of isoscalar and isovector resonances in the dipole channel at low energies. We predict that 22O and 24O have low-energy isoscalar quadrupole resonances at energies lower than 5 MeV.

  19. Nuclear Magnetic Resonance spectroscopy studies of proteins-glycoconjugates interactions

    OpenAIRE

    Marchetti, Roberta

    2013-01-01

    This PhD thesis work has been focused on the analysis of the structural requisites for recognition and binding between proteins and glycoconjugates, essential for the comprehension of mechanisms of paramount importance in chemistry, biology and biomedicine. A large variety of techniques, such as crystallographic analysis, titration microcalorimetry (ITC), surface plasmon resonance (SPR) and fluorescence spectroscopy, allows the elucidation of molecular recognition events. In the last years...

  20. Direct vs statistical decay of nuclear giant multipole resonances

    International Nuclear Information System (INIS)

    Hussein, M.S.

    1986-07-01

    A theoretical framework for the description of the decay of giant multipole resonances is developed. Besides the direct decay, both the pre-equilibrium and statistical (compound) decays are taken into account in a consistent way. It is shown that the statistical decay of the GR is not necessarily correctly described by the Hauser-Feshbach theory owing to the presence of a mixing parameter, which measures the degree of fragmentation. Applications are made to several cases. (Author) [pt

  1. Value of nuclear magnetic resonance imaging in cardiology

    International Nuclear Information System (INIS)

    Cabon-Martin, C.

    1987-01-01

    The present study summarizes an experience with Magnetic Resonance Imaging (MRI) in the evaluation of twelve patients with a variety of cardiac abnormalities (myocardial infarction, mural thrombi, obstructive cardiomyopathy, pericarditis). The results are compared with clinical data, with measurements from other techniques such as two-dimensional echocardiography and with the images in normal subjects. An anticipated advantage of MRI is the ability to provide better tissue characterization, than has been attained with other imaging techniques, by relaxation time measurement [fr

  2. Enhanced nuclear magnetic resonance in a non-magnetic cubic doublet

    International Nuclear Information System (INIS)

    Veenendaal, E.J.

    1982-01-01

    In this thesis two lanthanide compounds are studied which show enhanced nuclear magnetism at low temperatures: Rb 2 NaHoF 6 and CsNaHoF 6 . Chapter II gives a description of the 4 He-circulating refrigerator, which was built to provide the low temperatures required for the polarization of the enhanced nuclear moments. This type of dilution refrigerator was chosen because of its simple design and large cooling power. Chapter III is devoted to a comparison of the different types of dilution refrigerators. A theoretical discussion is given of their performance, starting from the differential equations, which govern the temperature distribution in the refrigerator. In chapter IV the actual performance of the refrigerator, described in chapter II is discussed. In chapter V a description of the NMR-apparatus, developed for very-low-temperature NMR experiments is given. In chapter VI experimental results on the compound Rb 2 NaHoF 6 are presented. The CEF-ground state of this compound is probably the non-magnetic doublet GAMMA 3 , but at a temperature of 170 K a structural phase transition lowers the crystal symmetry from cubic to tetragonal and the doublet is split into two singlets. In chapter VII specific heat, (enhanced) nuclear magnetic resonance and magnetization measurements on the compound Cs 2 NaHoF 6 are presented which also has a GAMMA 3 -doublet ground state. In zero magnetic field the degeneracy of the doublet is removed at a temperature of 393 mK, where a phase transition is induced by quadrupolar interactions. (Auth.)

  3. A neutron irradiator to perform nuclear activation

    International Nuclear Information System (INIS)

    Zamboni, C. B.; Zahn, G.S.; Figueredo, A. M. G.; Madi, T. F.; Yoriyaz, H.; Lima, R. B.; Shtejer, K.; Dalaqua Jr, L.

    2001-01-01

    The development of appropriate nuclear instrumentation to perform neutron activation analyze (NAA), using thermal and fast neutrons, can be useful to investigate materials outside the reactor premises. Considering this fact, a small size neutron irradiator prototype was developed at IPEN facilities (Instituto de Pesquisas Energeticas e Nucleares - Brazil). Basically, this prototype consists of a cylinder of 1200 mm long and 985 mm diameter (filled with paraffin) with two Am-Be sources (600GBq each) arranged in the longitudinal direction of its geometric center. The material to be irradiated is positioned at a radial direction of the cylinder between the two Am-Be sources. The main advantage of this irradiator is a very stable neutron flux eliminating the use of standard material (measure of the induced activity in the sample by comparative method). This way the process became agile, practical and economic, but quantities at mg levels of samples are necessary to achieve good sensitivity, when the material has a low microscopy neutron cross section. As fast and thermal neutron can be used, the flux distribution, for both, were calculated and the prototype performance is discussed

  4. Unraveling multi-spin effects in rotational resonance nuclear magnetic resonance using effective reduced density matrix theory

    International Nuclear Information System (INIS)

    SivaRanjan, Uppala; Ramachandran, Ramesh

    2014-01-01

    A quantum-mechanical model integrating the concepts of reduced density matrix and effective Hamiltonians is proposed to explain the multi-spin effects observed in rotational resonance (R 2 ) nuclear magnetic resonance (NMR) experiments. Employing this approach, the spin system of interest is described in a reduced subspace inclusive of its coupling to the surroundings. Through suitable model systems, the utility of our theory is demonstrated and verified with simulations emerging from both analytic and numerical methods. The analytic results presented in this article provide an accurate description/interpretation of R 2 experimental results and could serve as a test-bed for distinguishing coherent/incoherent effects in solid-state NMR

  5. Unraveling multi-spin effects in rotational resonance nuclear magnetic resonance using effective reduced density matrix theory

    Energy Technology Data Exchange (ETDEWEB)

    SivaRanjan, Uppala; Ramachandran, Ramesh, E-mail: rramesh@iisermohali.ac.in [Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, Manauli, P.O. Box-140306, Mohali, Punjab (India)

    2014-02-07

    A quantum-mechanical model integrating the concepts of reduced density matrix and effective Hamiltonians is proposed to explain the multi-spin effects observed in rotational resonance (R{sup 2}) nuclear magnetic resonance (NMR) experiments. Employing this approach, the spin system of interest is described in a reduced subspace inclusive of its coupling to the surroundings. Through suitable model systems, the utility of our theory is demonstrated and verified with simulations emerging from both analytic and numerical methods. The analytic results presented in this article provide an accurate description/interpretation of R{sup 2} experimental results and could serve as a test-bed for distinguishing coherent/incoherent effects in solid-state NMR.

  6. Nuclear Power Plant Performance: Ascending The Summit

    International Nuclear Information System (INIS)

    Anderson, T. M.

    1986-01-01

    When we look back over the years and consider the progress we have made in improving nuclear plant performance, I'm sure that many of you must feel the same mixture of elation and apprehension the mountain climber feels when he finally confronts his summit. In the curse of the last 10 years, many of US have watched availability averages rise from 50% to 60%, to 65% -- and recently, to 70%, 80% and beyond. Yet, as impressive an accomplishment as that is, there comes, I think, a growing realization that the steady increases we have achieved up to now may, in fact, have been the easy part of the journey, the trek from base camp -- and that within a very small handful of years, we may find ourselves pushing plant performance right to the limit, only to discover that it is pushing back

  7. On the safety performance of the advanced nuclear energy systems

    International Nuclear Information System (INIS)

    Li Shounan

    1999-01-01

    Some features on the safety performances of the Advanced Nuclear Energy Systems are discussed. The advantages and some peculiar problems on the safety of Advanced Nuclear Energy Systems with subcritical nuclear reactor driven by external neutron sources are also pointed out in comparison with conventional nuclear reactors

  8. Nuclear magnetic resonance J coupling constant polarizabilities of hydrogen peroxide

    DEFF Research Database (Denmark)

    Kjær, Hanna; Nielsen, Monia R.; Pagola, Gabriel I.

    2012-01-01

    In this paper we present the so far most extended investigation of the calculation of the coupling constant polarizability of a molecule. The components of the coupling constant polarizability are derivatives of the NMR indirect nuclear spin-spin coupling constant with respect to an external elec...

  9. Nuclear magnetic resonance common laboratory, quadrennial report; Laboratoire commun de resonance magnetique nucleaire, rapport quadriennal 1994-1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    This quadrennial report of the nuclear magnetic resonance common laboratory gives an overview of the main activities. Among the different described activities, only one is interesting for the INIS database: it concerns the Solid NMR of cements used for radioactive wastes storage. In this case, the NMR is used to characterize the structure of the material and the composition, structure and kinetics of formation of the alteration layer which is formed at the surface of concrete during water leaching conditions. The NMR methodology is given. (O.M.)

  10. Fission decay properties of nuclear giant multipole resonances

    International Nuclear Information System (INIS)

    Dias, H.; Arruda Neto, J.D.T.; Hussein, M.S.; Carlson, B.V.

    1986-05-01

    The statistical fission decay properties of the giant dipole, quadrupole and monopole resonances in 236 U are investigated with the aid of the Hauser-Feshbach model. It is found, contrary to several recent claims, that the GQR fission decay probability is as large as that of the GDR, at energies higher than the fission barrier. At energies close to the f.b., the GQR fission probability is found to be appreciably larger than that of the GDR. The GMR fission probability follows closely that of the GQR. (Author) [pt

  11. Microcomputer simulation of nuclear magnetic resonance imaging contrasts

    International Nuclear Information System (INIS)

    Le Bihan, D.

    1985-01-01

    The high information content of magnetic resonance images is due to the multiplicity of its parameters. However, this advantage introduces a difficulty in the interpretation of the contrast: an image is strongly modified according to the visualised parameters. The author proposes a micro-computer simulation program. After recalling the main intrinsic and extrinsic parameters, he shows how the program works and its interest as a pedagogic tool and as an aid for contrast optimisation of images as a function of the suspected pathology [fr

  12. Characterization of lipid rafts in human platelets using nuclear magnetic resonance: A pilot study

    Directory of Open Access Journals (Sweden)

    Joshua F. Ceñido

    2017-07-01

    Full Text Available Lipid microdomains (‘lipid rafts’ are plasma membrane subregions, enriched in cholesterol and glycosphingolipids, which participate dynamically in cell signaling and molecular trafficking operations. One strategy for the study of the physicochemical properties of lipid rafts in model membrane systems has been the use of nuclear magnetic resonance (NMR, but until now this spectroscopic method has not been considered a clinically relevant tool. We performed a proof-of-concept study to test the feasibility of using NMR to study lipid rafts in human tissues. Platelets were selected as a cost-effective and minimally invasive model system in which lipid rafts have previously been studied using other approaches. Platelets were isolated from plasma of medication-free adult research participants (n=13 and lysed with homogenization and sonication. Lipid-enriched fractions were obtained using a discontinuous sucrose gradient. Association of lipid fractions with GM1 ganglioside was tested using HRP-conjugated cholera toxin B subunit dot blot assays. 1H high resolution magic-angle spinning nuclear magnetic resonance (HRMAS NMR spectra obtained with single-pulse Bloch decay experiments yielded spectral linewidths and intensities as a function of temperature. Rates of lipid lateral diffusion that reported on raft size were measured with a two-dimensional stimulated echo longitudinal encode-decode NMR experiment. We found that lipid fractions at 10–35% sucrose density associated with GM1 ganglioside, a marker for lipid rafts. NMR spectra of the membrane phospholipids featured a prominent ‘centerband’ peak associated with the hydrocarbon chain methylene resonance at 1.3 ppm; the linewidth (full width at half-maximum intensity of this ‘centerband’ peak, together with the ratio of intensities between the centerband and ‘spinning sideband’ peaks, agreed well with values reported previously for lipid rafts in model membranes. Decreasing

  13. Principles of nuclear magnetic resonance (NMR) - current state of the art

    International Nuclear Information System (INIS)

    Lerski, R.A.

    1985-01-01

    Nuclear magnetic resonance (NMR) imaging has progressed rapidly from laboratory curiosity to commercial exploitation and clinical application in the space of only three years. The physical principles underlying the technique are described and the equipment requirements outlined. The question of optimal magnetic field strength is discussed. (author)

  14. Time-domain, nuclear-resonant, forward scattering: the classical approach

    International Nuclear Information System (INIS)

    Hoy, G.R.

    1997-01-01

    This paper deals with the interaction of electromagnetic radiation with matter assuming the matter to have nuclear transitions in resonance with incident electromagnetic radiation. The source of the radiation is taken to be of two types; natural radioactive gamma decay and synchrotron radiation. Numerical examples using 57 Fe are given for the two types of source radiation. Calculated results are contrasted for the two cases. Electromagnetic radiation produced by recoil-free gamma-ray emission has essentially the natural linewidth. Electromagnetic radiation from a synchrotron, even with the best monochromators available, has a relatively broad-band spectrum, essentially constant for these considerations. Polarization effects are considered. In general, the nuclear-resonant medium changes the polarization of the input radiation on traversing the medium. Calculations are presented to illustrate that synchrotron radiation studies using nuclear-resonant forward scattering have the potential for making high-precision measurements of hyperfine fields and recoilless fractions. An interesting aspect of nuclear-resonant forward scattering, relative to possible gamma-ray laser development, is the so-called 'speed-up' effect

  15. Phosphorus-doped thin silica films characterized by magic-angle spinning nuclear magnetic resonance spectroscopy

    DEFF Research Database (Denmark)

    Jacobsen, H.J.; Skibsted, J.; Kristensen, Martin

    2001-01-01

    Magic-angle spinning nuclear magnetic resonance spectra of 31P and 29Si have been achieved for a thin silica film doped with only 1.8% 31P and deposited by plasma enhanced chemical vapor deposition on a pure silicon wafer. The observation of a symmetric 31P chemical shift tensor is consistent...

  16. Ga nuclear magnetic resonance study of UTGa5(T = Ni,Pt)

    International Nuclear Information System (INIS)

    Kato, Harukazu; Sakai, Hironori; Tokunaga, Yo; Tokiwa, Yoshihumi; Ikeda, Shugo; Onuki, Yoshichika; Kambe, Shinsaku; Walstedt, Russell E

    2003-01-01

    Ga nuclear magnetic resonance measurements have been carried out for the 5f antiferromagnets UNiGa 5 and UPtGa 5 . The transferred field at the Ga nuclei has been evaluated. The magnetic structure in the antiferromagnetic region has been confirmed from the microscopic point of view. The mechanism of the hyperfine interaction is discussed

  17. Hepatic Metabolism of Perfluorinated Carboxylic Acids and Polychlorotrifluoroethylene: A Nuclear Magnetic Resonance Investigation in vito

    Science.gov (United States)

    1994-01-06

    L. Narayanan. and B. M. Jamot. ’Effects of Peulluoro-n- octanoic Acid , Perfluoro-n-decanoic Acid , and Clofibrate on Hepatic Phosphorus Metabolism in...pathways and examined the impact of perfluorocarboxylic acid exposure. This investigative strategy will delineate the metabolic effices exerted by...Perfluorinated Carboxylic Acids and Polychlorotrifluoroethylene: A Nuclear Magnetic Resonance Investigation in Vivo Principal Investigator: Nicholas V. Reo

  18. Nuclear data project in Korea and resonance parameter evaluation of fission products

    International Nuclear Information System (INIS)

    Chang, Jonghwa; Oh, Soo-Youl

    2000-01-01

    Nuclear data activities in the fields of evaluation, processing, measurement, and service in Korea are presented in this paper. As one of the current activities, the neutron resonance parameters for stable or long-lived nineteen fission products have been evaluated and the results are presented here. (author)

  19. Nuclear magnetic resonance and the question of 5F electron localization in the actinides

    International Nuclear Information System (INIS)

    Fradin, F.Y.

    1976-01-01

    Nuclear magnetic resonance results are presented for a number of NaCl-type compounds and cubic Laves-phase type compounds of uranium, neptunium, and plutonium. Special emphasis is placed on the Knight shift and spin-lattice relaxation time measurements and their interpretation in terms of localized or itinerant pictures of the 5Line integral electrons

  20. Rheo-NMR: nuclear magnetic resonance and the rheology of complex fluids

    International Nuclear Information System (INIS)

    Callaghan, Paul T.

    1999-01-01

    The application of nuclear magnetic resonance methods to the study of complex fluids under shearing and extensional flows is reviewed. Both NMR velocimetry and spectroscopy approaches are discussed while specific systems studied include polymer melts, rigid rod and random coil polymers in solution, lyotropic and thermotropic liquid crystals and liquid crystalline polymers, and wormlike micelles. Reference is made to food systems. (author)

  1. Aspects of the engineering design of whole-body nuclear magnetic resonance machines

    International Nuclear Information System (INIS)

    Young, I.R.; Collins, A.G.; Hall, A.S.; Harman, R.R.; Butson, P.C.; Gilderdale, D.J.

    1987-01-01

    The paper on whole-body nuclear magnetic resonance machines reviews the basic physics very briefly, then examines the design requirements and engineering constraints for the major components of such a system. The paper concludes with a brief resume of the techniques used, and a short presentation of the type of results that are achieved. (author)

  2. In situ nuclear magnetic resonance study of defect dynamics during deformation of materials

    NARCIS (Netherlands)

    Murty, K.L.; Detemple, K.; Kanert, O.; Peters, G; de Hosson, J.T.M.

    1996-01-01

    Nuclear magnetic resonance techniques can be used to monitor in situ the dynamical behaviour of point and line defects in materials during deformation. These techniques are non-destructive and non-invasive. We report here the atomic transport, in particular the enhanced diffusion during deformation

  3. A Noninvasive Method to Study Regulation of Extracellular Fluid Volume in Rats Using Nuclear Magnetic Resonance

    Science.gov (United States)

    Time-domain nuclear magnetic resonance (TD-NMR)-based measurement of body composition of rodents is an effective method to quickly and repeatedly measure proportions of fat, lean, and fluid without anesthesia. TD-NMR provides a measure of free water in a living animal, termed % f...

  4. Measurement of single electron and nuclear spin states based on optically detected magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Berman, Gennady P [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Bishop, Alan R [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Chernobrod, Boris M [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Hawley, Marilyn E [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Brown, Geoffrey W [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Tsifrinovich, Vladimir I [Polytechnic University, Brooklyn, NY 11201 (United States)

    2006-05-15

    A novel approach for measurement of single electron and nuclear spin states is suggested. Our approach is based on optically detected magnetic resonance in a nano-probe located at the apex of an AFM tip. The method provides single electron spin sensitivity with nano-scale spatial resolution.

  5. Measurement of single electron and nuclear spin states based on optically detected magnetic resonance

    International Nuclear Information System (INIS)

    Berman, Gennady P; Bishop, Alan R; Chernobrod, Boris M; Hawley, Marilyn E; Brown, Geoffrey W; Tsifrinovich, Vladimir I

    2006-01-01

    A novel approach for measurement of single electron and nuclear spin states is suggested. Our approach is based on optically detected magnetic resonance in a nano-probe located at the apex of an AFM tip. The method provides single electron spin sensitivity with nano-scale spatial resolution

  6. Sc-45 nuclear magnetic resonance analysis of precipitation in dilute Al-Sc alloys

    NARCIS (Netherlands)

    Celotto, S; Bastow, TJ

    Nuclear magnetic resonance (NMR) with Sc-45 is used to determine the solid solubility of scandium in aluminium and to follow the precipitation of Al3Sc during the ageing of an Al-0.06 at.% Sc alloy via the two fully resolved peaks, corresponding to Sc in the solid solution Al matrix and to Sc in the

  7. Principles of nuclear magnetic resonance imaging using an inhomogeneous polarizing field

    International Nuclear Information System (INIS)

    Briguet, A.; Chaillout, J.; Goldman, M.

    1985-01-01

    In this paper, it is indicated how to reconstruct nuclear magnetic resonance images acquired in an inhomogeneous static magnetic field without the previous knowledge of its spatial distribution. The method provides also the map of the static magnetic field through the sample volume; furthermore it allows the use of non uniform but spatially controlled encoding gradients [fr

  8. Development of atomic-beam resonance method to measure the nuclear moments of unstable nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, T., E-mail: sugimoto@ribf.riken.jp [SPring-8 (Japan); Asahi, K. [Tokyo Institute of Technology, Department of Physics (Japan); Kawamura, H.; Murata, J. [Rikkyo University, Department of Physics (Japan); Nagae, D.; Shimada, K. [Tokyo Institute of Technology, Department of Physics (Japan); Ueno, H.; Yoshimi, A. [RIKEN Nishina Center (Japan)

    2008-01-15

    We have been working on the development of a new technique of atomic-beam resonance method to measure the nuclear moments of unstable nuclei. In the present study, an ion-guiding system to be used as an atomic-beam source have been developed.

  9. Quantification of lipoprotein profiles by nuclear magnetic resonance spectroscopy and multivariate data analysis

    DEFF Research Database (Denmark)

    Aru, Violetta; Lam, Chloie; Khakimov, Bekzod

    2017-01-01

    Lipoproteins and their subfraction profiles have been associated to diverse diseases including Cardio Vascular Disease (CVD). There is thus a great demand for measuring and quantifying the lipoprotein profile in an efficient and accurate manner. Nuclear Magnetic Resonance (NMR) spectroscopy is un...

  10. Interaction between adrenaline and dibenzo-18-crown-6: Electrochemical, nuclear magnetic resonance, and theoretical study

    Science.gov (United States)

    Yu, Zhang-Yu; Liu, Tao; Wang, Xue-Liang

    2014-12-01

    The interaction between adrenaline (Ad) and dibenzo-18-crown-6 (DB18C6) was studied by cyclic voltammetry, nuclear magnetic resonance spectroscopy, and the theoretical calculations, respectively. The results show that DB18C6 will affect the electron transfer properties of Ad. DB18C6 can form stable supramolecular complexes with Ad through ion-dipole and hydrogen bond interactions.

  11. Structure and dynamics of paramagnetic transients by pulsed EPR and NMR detection of nuclear resonance

    International Nuclear Information System (INIS)

    Trifunac, A.D.

    1981-01-01

    Structure and dynamics of transient radicals in pulse radiolysis can be studied by time resolved EPR and NMR techniques. EPR study of kinetics and relaxation is illustrated. The NMR detection of nuclear resonance in transient radicals is a new method which allows the study of hyperfine coupling, population dynamics, radical kinetics, and reaction mechanism. 9 figures

  12. 19F-nuclear magnetic resonance spectroscopy as a tool to ...

    African Journals Online (AJOL)

    19F-nuclear magnetic resonance spectroscopy as a tool to investigate host-guest complexation of some antidepressant drugs with natural and modified cyclodextrins. Leila Shafiee Dastjerdi1* and Mojtaba Shamsipur2. 1Faculty of Science, Roudehen Branch, Islamic Azad University, Tehran, 2Department of Chemistry, ...

  13. Nuclear magnetic resonance spectroscopy of living systems : Applications in comparative physiology

    NARCIS (Netherlands)

    VanDenThillart, G; VanWaarde, A

    The most attractive feature of nuclear magnetic resonance spectroscopy (MRS) is the noninvasive and nondestructive measurement of chemical compounds in intact tissues. MRS already has many applications in comparative physiology, usually based on observation of P-31, since the levels of phosphorus

  14. Display of cross sectional anatomy by nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Hinshaw, W.S.; Andrew, E.R.; Bottomley, P.A.; Holland, G.N.; Moore, W.S.; Worthington, B.S.

    1978-01-01

    High definition cross-sectional images produced by a new nuclear magnetic resonace (NMR) technique are shown. The images are a series of thin section scans in the coronal plane of the head of a rabbit. The NMR images are derived from the distribution of the density of mobile hydrogen atoms. Various tissue types can be distinguished and a clear registration of gross anatomy is demonstrated. No known hazards are associated with the technique. (author)

  15. Carbon and deuterium nuclear magnetic resonance in solids

    Energy Technology Data Exchange (ETDEWEB)

    Shattuck, Thomas Wayne [Univ. of California, Berkeley, CA (United States)

    1976-07-01

    In Chapter I we present the results on a study of cross polarization dynamics, between protons and carbon-13 in adamantane, by the direct observation of the dilute, carbon-13, spins. These dynamics are an important consideration in the efficiency of proton enhancement double-resonance techniques and they also provide good experimental models for statistical theories of cross relaxation. In order to test these theories we present a comparison of the experimental and theoretical proton dipolar fluctuation correlation time τc, which is experimentally 110 ± 15 μsec and theoretically 122 μsec for adamantane. These double resonance considerations provide the background for extensions to deuterium and double quantum effects discussed in Chapter II. In Chapter II an approach to high resolution nmr of deuterium in solids is described. The m = 1 → -1 transition is excited by a double quantum process and the decay of coherence Q(τ) is monitored. Fourier transformation yields a deuterium spectrum devoid of quadrupole splittings and broadening. If the deuterium nuclei are dilute and the protons are spin decoupled, the double-quantum spectrum is a high resolution one and yields information on the deuterium chemical shifts Δω. The relationship Q(τ) ~ cos 2Δωτ is checked and the technique is applied to a single crystal of oxalic acid dihydrate enriched to ~ 10% in deuterium. The carboxyl and the water deuterium shifts are indeed resolved and the anisotropy of the carboxyl shielding tensor is estimated to be Δσ = 32 ± 3 ppm. A complete theoretical analysis is presented. The extension of cross relaxation techniques, both direct and indirect, to proton-deuterium double resonance is also described. The m = 1 → -1 double quantum transition and the m = ± 1 → 0 single quantum transitions may all be polarized and we present the derivation of the Hartmann-Hahn cross polarization conditions for each case. In addition the dynamics of the double quantum process

  16. Mechanical design parameters for detection of nuclear signals by magnetic resonance force microscopy

    International Nuclear Information System (INIS)

    Moore, G.J.; Hanlon, J.A.; Lamartine, B.; Hawley, M.; Solem, J.C.; Signer, S.; Jarmer, J.J.; Penttila, S.; Sillerud, L.O.; Pryputniewicz, R.J.

    1993-01-01

    Recent theoretical work has shown that mechanical detection of magnetic resonance from a single nuclear spin is in principle possible. This theory has recently been experimentally validated by the mechanical detection of electron spin resonance signals using microscale cantilevers. Currently we are extending this technology in an attempt to detect nuclear signals which are extending this technology in an attempt to detect nuclear signals which are three orders of magnitude lower in intensity than electron signals. In order to achieve the needed thousand-fold improvement in sensitivity we have undertaken the development of optimized mechanical cantilevers and highly polarized samples. Finite element modeling is used as a tool to simulate cantilever beam dynamics and to optimize the mechanical properties including Q, resonant frequency, amplitude of vibration and spring constant. Simulations are compared to experiments using heterodyne hologram interferometry. Nanofabrication of optimized cantilevers via ion milling will be directed by the outcome of these simulations and experiments. Highly polarized samples are developed using a three-fold approach: (1) high magnetic field strength (2.5T), (2) low temperature (1K), and (3) use of samples polarized by dynamic nuclear polarization. Our recent experiments have demonstrated nuclear polarizations in excess of 50% in molecules of toulene

  17. A nuclear magnetic resonance study of (TMTSF) 2PF 6

    Science.gov (United States)

    McBrierty, V. J.; Douglass, D. C.; Wudl, F.

    1982-09-01

    Inverse linewidths and spin-lattice relaxation times of fluorine and proton magnetic resonance spectra are used to examine molecular motion in the organic superconductor (TMTSF) 2PF 6. The results clearly show that rotation of the PF 6- anion is the principal agent for the observed relaxation of fluorine contrary to some suggestions in the current literature. This interpretation is based upon qualitative comparison with relaxation in plastic crystals, where molecular rotation is well characterized, and upon the quantitative agreement between the calculated and observed linewidth change near 90K and the maximum spin-lattice relaxation rate at 140K. There is also motional evidence, supported by X-ray structure measurements, that a phase transition occurs in the vicinity of 160K.

  18. Phase-space exploration in nuclear giant resonance decay

    International Nuclear Information System (INIS)

    Drozdz, S.; Nishizaki, S.; Wambach, J.; Speth, J.

    1995-01-01

    The rate of phase-space exploration in the decay of isovector and isoscalar giant quadrupole resonances in 40 Ca is analyzed. The study is based on the time dependence of the survival probability and of the spectrum of generalized entropies evaluated in the space of one-particle--one-hole (1p-1h) and 2p-2h states. Three different cases for the level distribution of 2p-2h background states, corresponding to (a) high degeneracy, (b) classically regular motion, and (c) classically chaotic motion, are studied. In the latter case the isovector excitation evolves almost statistically while the isoscalar excitation remains largely localized, even though it penetrates the whole available phase space

  19. Development of nuclear magnetic resonance tomography technology - TORM

    International Nuclear Information System (INIS)

    Tannus, A.

    1987-01-01

    The development of hardware and software necessary to implement the Magnetic Resonance Imaging (MRI) techniques is described. The major subjects were the construction of an aquisition and control system which allowed the operation of a pulsed Fourier NMR spectrometer as a NMR Tomograph; further it was oriented the developing of a NMR spectrometer whose parameters could be easily reconfigured by the controlling system. As a result a sofisticated equipment which allows, more than the proposed, working with high resolution spectroscopic techniques and spectroscopy in solids, was obtained. Since the basic techniques employed in NMR and CT Tomographs are well known, a great emphasis was also given on the understanding of the image reconstruction techniques that constitutes today the frontier of research in this area. The results obtained with the system described here are considered good, comparable to the results from commercial units developed in cooperation with imaging groups located in universities abroad. (author) [pt

  20. Measurement of Charged Pions from Neutrino-produced Nuclear Resonance

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Clifford N. [Univ. of California, Irvine, CA (United States)

    2014-01-01

    A method for identifying stopped pions in a high-resolution scintillator bar detector is presented. I apply my technique to measure the axial mass MΔAfor production of the Δ(1232) resonance by neutrino, with the result MΔA = 1.16±0.20 GeV (68% CL) (limited by statistics). The result is produced from the measured spectrum of reconstructed momentum-transfer Q2. I proceed by varying the value of MΔA in a Rein-Sehgal-based Monte Carlo to produce the best agreement, using shape only (not normalization). The consistency of this result with recent reanalyses of previous bubble-chamber experiments is discussed.

  1. Resonant ionization by laser beams: application to ions sources and to study the nuclear structure of radioactive tellurium isotopes

    International Nuclear Information System (INIS)

    Sifi, R.

    2007-07-01

    The radioactive ion beams that are produced through current isotope separators are well separated according to the A mass but not according to the Z parameter. The resonant ionization through laser beams applied to ion sources allows the production of radioactive ion beam in a very selective and efficient way by eliminating the isobaric contamination. The first chapter is dedicated to the resonant ionization by laser beams, we describe the principle, the experimental setting, the lasers used, the ionization schemes and the domain of application. The second chapter deals with the application of resonant ionization to laser ion sources for the production of radioactive ion beams. We present experimental tests performed for getting copper ion beams. Resonant ionization through laser is also used in the spectroscopy experiments performed at the Isolde (isotope separation on-line device) installation in CERN where more than 20 elements are ionized very efficiently. The technique is based on a frequency scanning around the excitation transition of the atoms in order to probe the hyperfine structure. Laser spectroscopy allows the determination of the hyperfine structure as well as the isotopic shift of atoms. In the third chapter the method is applied to the spectroscopy of tellurium atoms. First, we define the 2 parameters on which the extraction is based: charge radius and nuclear moments, then we present several theoretical models that we have used to assess our experimental results. (A.C.)

  2. Nuclear magnetic resonance detection and spectroscopy of single proteins using quantum logic.

    Science.gov (United States)

    Lovchinsky, I; Sushkov, A O; Urbach, E; de Leon, N P; Choi, S; De Greve, K; Evans, R; Gertner, R; Bersin, E; Müller, C; McGuinness, L; Jelezko, F; Walsworth, R L; Park, H; Lukin, M D

    2016-02-19

    Nuclear magnetic resonance spectroscopy is a powerful tool for the structural analysis of organic compounds and biomolecules but typically requires macroscopic sample quantities. We use a sensor, which consists of two quantum bits corresponding to an electronic spin and an ancillary nuclear spin, to demonstrate room temperature magnetic resonance detection and spectroscopy of multiple nuclear species within individual ubiquitin proteins attached to the diamond surface. Using quantum logic to improve readout fidelity and a surface-treatment technique to extend the spin coherence time of shallow nitrogen-vacancy centers, we demonstrate magnetic field sensitivity sufficient to detect individual proton spins within 1 second of integration. This gain in sensitivity enables high-confidence detection of individual proteins and allows us to observe spectral features that reveal information about their chemical composition. Copyright © 2016, American Association for the Advancement of Science.

  3. Development of nuclear fuel rod inspection technique using ultrasonic resonance phenomenon

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Myung Sun; Lee, Jong Po; Ju, Young Sang [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-11-01

    Acoustic resonance scattering from a nuclear fuel rod in water is analyzed. A new model for the background which is attributed to the interference of reflected wave and diffracted wave is found and here named {sup t}he inherent background{sup .} The resonance spectrum of a fuel rod is obtained by subtracting the inherent background from the scattered pressure. And also analyzed are the effect of material damping of cladding tube and pellet on the resonance spectrum of a fuel rod. The propagation characteristics of circumferential waves which cause the resonances of cladding tube is produced and the appropriate resonance modes for the application to the inspection of assembled fuel rods are selected. The resonance modes are experimentally measured for pre- and post-irradiated fuel rods and the validation of the fuel rod inspection using ultrasonic resonance phenomenon is examined. And thin ultrasonic sensors accessible into the narrow interval (about 2-3mm) between assembled fuel rods are designed and manufactured. 14 refs. (Author).

  4. Sensing performance analysis on Fano resonance of metallic double-baffle contained MDM waveguide coupled ring resonator

    Science.gov (United States)

    Chen, Ying; Luo, Pei; Liu, Xiaofei; Di, Yuanjian; Han, Shuaitao; Cui, Xingning; He, Lei

    2018-05-01

    Based on the transmission property and the photon localization characteristic of the surface plasmonic sub-wavelength structure, a metallic double-baffle contained metal-dielectric-metal (MDM) waveguide coupled ring resonator is proposed. Like the electromagnetically induced transparency (EIT), the Fano resonance can be achieved by the interference between the metallic double-baffle resonator and the ring resonator. Based on the coupled mode theory, the transmission property is analyzed. Through the numerical simulation by the finite element method (FEM), the quantitative analysis on the influences of the radius R of the ring and the coupling distance g between the metallic double-baffle resonator and the ring resonator for the figure of merit (FOM) is performed. And after the structure parameter optimization, the sensing performance of the waveguide structure is discussed. The simulation results show that the FOM value of the optimized structure can attain to 5.74 ×104 and the sensitivity of resonance wavelength with refractive index drift is about 825 nm/RIU. The range of the detected refractive index is suitable for all gases. The waveguide structure can provide effective theoretical references for the design of integrated plasmonic devices.

  5. Pulsed magnetic field generation suited for low-field unilateral nuclear magnetic resonance systems

    Science.gov (United States)

    Gaunkar, Neelam Prabhu; Selvaraj, Jayaprakash; Theh, Wei-Shen; Weber, Robert; Mina, Mani

    2018-05-01

    Pulsed magnetic fields can be used to provide instantaneous localized magnetic field variations. In presence of static fields, pulsed field variations are often used to apply torques and in-effect to measure behavior of magnetic moments in different states. In this work, the design and experimental performance of a pulsed magnetic field generator suited for low static field nuclear magnetic resonance (NMR) applications is presented. One of the challenges of low bias field NMR measurements is low signal to noise ratio due to the comparable nature of the bias field and the pulsed field. Therefore, a circuit is designed to apply pulsed currents through an inductive load, leading to generation of pulsed magnetic fields which can temporarily overpower the effect of the bias field on magnetic moments. The designed circuit will be tuned to operate at the precession frequency of 1H (protons) placed in a bias field produced by permanent magnets. The designed circuit parameters may be tuned to operate under different bias conditions. Therefore, low field NMR measurements can be performed for different bias fields. Circuit simulations were used to determine design parameters, corresponding experimental measurements will be presented in this work.

  6. Human performance in the nuclear industry

    International Nuclear Information System (INIS)

    Koncz, Steven M.

    2015-01-01

    Management of employees human performance in the Nuclear Industry is endemic to their safety when working. In the United Kingdom it has been a key focus since 2003. Employees were made aware through a detailed program of workshops, of the error prevention methods and how to apply them. The use of effective incident barriers became embedded in the safety culture. The methodology implemented was personal ownership, to enable self assessment of behaviors, attitudes and beliefs. When put in place, there are many specific barriers, which can reduce the chances of an error occurring. They come under the headings of organisational, procedural and physical barriers. All of these were used in some way and continue to be reinforced on a daily basis. Specific barriers are applied in specific situations. However, some general ones are also effective. In common use are the Take 2 or Take 5 Minutes, point of work risk assessments. Applying the human performance barrier Independent Verification (I.V.) would result in 'Take 3 and I.V.' This would independently double check the risk assessment. New ways of thinking are required to continuously improve and evolve. Results of the error reduction process included; reduced workload, increased plant reliability, efficiencies and productivity. (author)

  7. Human performance in the nuclear industry

    International Nuclear Information System (INIS)

    Koncz, S.M.

    2015-01-01

    Management of employees human performance in the Nuclear Industry is endemic to their safety when working. In the United Kingdom it has been a key focus since 2003. Employees were made aware through a detailed program of workshops, of the error prevention methods and how to apply them. The use of effective incident barriers became embedded in the safety culture. The methodology implemented was personal ownership, to enable self assessment of behaviors, attitudes and beliefs. When put in place, there are many specific barriers, which can reduce the chances of an error occurring. They come under the headings of organisational, procedural and physical barriers. All of these were used in some way and continue to be reinforced on a daily basis. Specific barriers are applied in specific situations. However, some general ones are also effective. In common use are the Take 2 or Take 5 Minutes, point of work risk assessments. Applying the human performance barrier Independent Verification (I.V.) would result in 'Take 3 and I.V.' This would independently double check the risk assessment. New ways of thinking are required to continuously improve and evolve. Results of the error reduction process included; reduced workload, increased plant reliability, efficiencies and productivity. (author)

  8. Hadronic atoms and ticklish nuclei: the E2 nuclear resonance effect

    International Nuclear Information System (INIS)

    Leon, M.

    1975-06-01

    The E2 nuclear resonance effect in hadronic atoms offers a way to increase the hadronic information that can be obtained from hadronic x-ray experiments. The effect occurs when an atomic deexcitation energy closely matches a nuclear excitation energy, so that some configuration mixing occurs. It shows up as an attenuation of some of the hadronic x-ray lines from a resonant versus a normal isotope target. The effect was observed very clearly in pionic cadmium in a recent LAMPF experiment. A planned LAMPF experiment will use the nuclear resonance effect to determine whether the p-wave π-nucleus interaction does indeed become repulsive for Z greater than or equal to 35 as predicted. The effect also appears in the kaonic molybdenum data taken at LBL because several of the stable molybdenum isotopes are resonant. A number of promising cases for π - , K - , anti p, and Σ - atoms are discussed and a spectacular and potentially very informative experiment on anti p- 100 Mo is proposed. (9 figures, 9 tables) (U.S.)

  9. Nuclear magnetic resonance of randomly diluted magnetic materials; Ressonancia nuclear magnetica em materiais magneticos diluidos aleatoriamente

    Energy Technology Data Exchange (ETDEWEB)

    Magon, C J

    1986-12-31

    The temperature dependence of the nuclear relaxation rates and line shapes of the F{sub O} resonance in the diluted antiferromagnet Fe{sub x} Zn{sub 1-x} F{sub 2} and Mn{sub x} Zn{sub 1-x} F{sub 2} are studied over a large temperature range T{sub N} < {approx} T {<=} 300 K. The high (room) temperature spin-lattice relaxation rates (1/T{sub 1}) of the F{sub O} nuclei, which are not transfer hyperfine coupled to the Fe (or Mn) spins, have been measured and calculated as a function of the concentration x. Good agreement with experiment is found for the theoretical results, which have been obtained in the range 0.1 {<=} x {<=} 0.8. The temperature dependence of 1/T{sub 1} for T{sub N}

  10. Nuclear Magnetic Resonance Imaging in Endodontics: A Review.

    Science.gov (United States)

    Di Nardo, Dario; Gambarini, Gianluca; Capuani, Silvia; Testarelli, Luca

    2018-04-01

    This review analyzes the increasing role of magnetic resonance imaging (MRI) in dentistry and its relevance in endodontics. Limits and new strategies to develop MRI protocols for endodontic purposes are reported and discussed. Eligible studies were identified by searching the PubMed databases. Only original articles on dental structures, anatomy, and endodontics investigated by in vitro and in vivo MRI were included in this review. Original articles on MRI in dentistry not concerning anatomy and endodontics were excluded. All the consulted studies showed well-defined images of pathological conditions such as caries and microcracks. The enhanced contrast of pulp provided a high-quality reproduction of the tooth shape and root canal in vitro and in vivo. Assessment of periapical lesions is possible even without the use of contrast medium. MRI is a nonionizing technique characterized by high tissue contrast and high image resolution of soft tissues; it could be considered a valid and safe diagnostic investigation in endodontics because of its potential to identify pulp tissues, define root canal shape, and locate periapical lesions. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  11. Flow imaging by means of nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Wedeen, V.J.; Rosen, B.R.

    1986-01-01

    To form an image (velocity profile) of fluid flowing in a vessel, the fluid is stimulated to produce a time-dependent magnetic resonance signal which is subjected to Fourier-transform. The stimulating is done so as to introduce spatially-dependent phase information indicative of the velocity profile of the fluid. Thus, for measuring velocity in the x-direction within a z-slice, after selective oxidation of the slice, a long gradient bsub(x), is applied, followed by a π pulse. A second frequency dispersing bsub(x) gradient bsub(x) is present in a period embracing the echo signal, following a phase encoding gradient bsub(y). Slice section may be omitted for projection imaging, and an image of fluid flow can be obtained by generating two data sets encoded with phase information indicative of two different velocity profiles of the fluid (taken at different times), combining the data sets, and displaying the resulting data set as an image. By analysing the signal over a period not centred at the middle of the echo signal, a frequency offset is introduced giving the image a striped appearance, the strips being curved in the presence of fluid flow. (author)

  12. Method of using a nuclear magnetic resonance spectroscopy standard

    Science.gov (United States)

    Spicer, Leonard D.; Bennett, Dennis W.; Davis, Jon F.

    1985-01-01

    (CH.sub.3).sub.3 SiNSO is produced by the reaction of ((CH.sub.3).sub.3 Si).sub.2 NH with SO.sub.2. Also produced in the reaction are ((CH.sub.3).sub.3 Si).sub.2 O and a new solid compound [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ]. Both (CH.sub.3).sub.3 SiNSO and [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ] have fluorescent properties. The reaction of the subject invention is used in a method of measuring the concentration of SO.sub.2 pollutants in gases. By the method, a sample of gas is bubbled through a solution of ((CH.sub.3).sub.3 Si).sub.2 NH, whereby any SO.sub.2 present in the gas will react to produce the two fluorescent products. The measured fluorescence of these products can then be used to calculate the concentration of SO.sub.2 in the original gas sample. The solid product [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ] may be used as a standard in solid state NMR spectroscopy, wherein the resonance peaks of either .sup.1 H, .sup.13 C, .sup.15 N, or .sup.29 Si may be used as a reference.

  13. The 132Sn giant dipole resonance as a constraint on nuclear matter properties

    Science.gov (United States)

    Roach, Brandon; Bonasera, Giacomo; Shlomo, Shalom

    2015-10-01

    Nuclear giant resonances provide a sensitive method for constraining the properties of nuclear matter (NM) - many of which have large uncertainties - and thereby improve the nuclear energy-density functional. In this work, self-consistent Hartree-Fock random-phase approximation (HF-RPA) theory was employed to calculate the strength function and energy of the isovector giant dipole resonance (IVGDR) in the doubly-magic 132Sn nucleus. Several (17) commonly-used Skyrme-type interactions were employed. The correlations between the IVGDR centroid energy and each nuclear matter property were explored, as were correlations between the nuclear matter properties and the 132Sn neutron skin thickness rn -rp . Experimental data for the IVGDR centroid energy was used to constrain the symmetry energy density, the symmetry energy, and its first and second derivatives, respectively, of NM. Further investigation, particularly of nuclides far from stability, will be needed to extend the nuclear energy-density functional to the extremes of density and neutron abundance found in neutron stars and astrophysical nucleosynthesis environments.

  14. Identification of a probable new adrenergic agonist by nuclear magnetic resonance and mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Boatto, Gianpiero [Department of Toxicological Chemistry, University of Sassari, Sassari (Italy); Culeddu, Nicola [CNR Biomolecular Chemistry Institute, Sassari (Italy); Testa, Cecilia [IZS della Sardegna, Sassari (Italy); Neri, Bruno [IZS delle Regioni Lazio e Toscana, Rome (Italy); Brambilla, Gianfranco [Istituto Superiore di Sanita, Environment Department, Toxicological Chemistry Unit, Rome (Italy)]. E-mail: g.brambi@iss.it; Barbosa, Jorge [LNIV, Lisbon (Portugal); Cruz, Clara [LNIV, Lisbon (Portugal)

    2007-03-14

    In animal production, it is consolidated the synthesis and the illegal use of growth promoters of new generation, able to skip routine screening and confirmatory analysis. In this work it is reported the nuclear magnetic resonance (NMR) and the mass spectrometry identification of a probable new adrenergic drug found in a feed premix. The substance was selectively purified on alpha 1 acid glycoprotein affinity columns; then its structure was first achieved by recording the {sup 13}C NMR spectrum that gave the total number of carbons of the molecule, successively sorted by DEPT experiments into quaternary, CH, CH{sub 2}, and CH{sub 3} groups. However, the complete assignments of all resonances were derived from the bi-dimensional analysis and the crucial indications from the {sup 1}H-{sup 13}C reverse experiments. Further characterisation was performed by atmospheric pressure chemical ionisation both in positive and negative ion mode, matching the molecular ion and the fragmentation pattern with those of most recently described new adrenergic agonists. After the loss of a ter-butylic group, the structure shows an internal symmetry along with the presence of Chlorine clusters. The proposed formula of the compound, the 8,8'-diamino-9,9'-dichloro-1-terbutyl-1,1',4,4-tetrahydro-5H,5'H-2,2'-bi -1-benzazepine-5,5'-dione, partially resembles that of Zilpaterol for the presence of a heterocyclic ring; Further work is in progress to characterise the structure-activity relationship.

  15. The TARC experiment (PS211): neutron-driven nuclear transmutation by adiabatic resonance crossing

    International Nuclear Information System (INIS)

    Revol, J.P.; Arnould, H.; Bompas, C.A.

    1999-01-01

    The main purpose of the TARC experiment is to demonstrate the possibility of using Adiabatic Resonance Crossing (ARC) to destroy efficiently Long-Lived Fission Fragments (LLFFs) in accelerator-driven systems and to validate a new simulation developed in the framework of the Energy Amplifier programme. An experimental set-up was installed in a CERN PS beam line to study how neutrons produced by spallation at relatively high energy (E n ≥1 MeV) slow down quasi adiabatically with almost flat isolethargic energy distribution and reach the capture resonance energy of an element to be transmuted where they will have a high probability of being captured. Precision measurements of energy and space distributions of spallation neutrons (using 2.5 GeV/c and 3.5 GeV/c protons) slowing down in a 3.3 m x 3.3 m x 3 m lead volume and of neutron capture rates of LLFFs 99 Tc, 129 I, and several other elements were performed. An appropriate formalism and appropriate computational tools necessary for the analysis and understanding of the data were developed and validated in detail. Our direct experimental observation of ARC demonstrates the possibility to destroy, in a parasitic mode, outside the Energy Amplifier core, large amounts of 99 Tc or 129 I at a rate exceeding the production rate, thereby making it practical to reduce correspondingly the existing stockpile of LLFFs. In addition, TARC opens up new possibilities for radioactive isotope production as an alternative to nuclear reactors, in particular for medical applications, as well as new possibilities for neutron research and industrial applications. (orig.)

  16. On the Fer expansion: Applications in solid-state nuclear magnetic resonance and physics

    Energy Technology Data Exchange (ETDEWEB)

    Mananga, Eugene Stephane, E-mail: esm041@mail.harvard.edu

    2016-01-18

    Theoretical approaches are useful and powerful tools for more accurate and efficient spin dynamics simulation to understand experiments and devising new RF pulse sequence in nuclear magnetic resonance. Solid-state NMR is definitely a timely topic or area of research, and not many papers on the respective theories are available in the literature of nuclear magnetic resonance or physics reports. This report presents the power and the salient features of the promising theoretical approach called Fer expansion that is helpful to describe the evolution of the spin system in nuclear magnetic resonance. The report presents a broad view of algorithms of spin dynamics based on the Fer expansion which provides procedures to control and describe the spin dynamics in solid-state NMR. Significant applications of the Fer expansion are illustrated in NMR and in physics such as classical physics, nonlinear dynamics systems, celestial mechanics and dynamical astronomy, hydrodynamics, nuclear, atomic, molecular physics, and quantum mechanics, quantum field theory, high energy physics, electromagnetism. The aim of this report is to bring to the attention of the spin dynamics community, the bridge that exists between solid-state NMR and other related fields of physics and applied mathematics.

  17. On the Floquet–Magnus expansion: Applications in solid-state nuclear magnetic resonance and physics

    Energy Technology Data Exchange (ETDEWEB)

    Mananga, Eugene Stephane, E-mail: emananga@gradcenter.cuny.edu [Harvard Medical School and Massachusetts General Hospital, Center for Advanced Medical Imaging Sciences, Division of Nuclear Medicine and Molecular Imaging Physics, Department of Radiology, 55 Fruit Street, Boston, Massachusetts 02114 (United States); Charpentier, Thibault, E-mail: thibault.charpentier@cea.fr [Commissariat à l’Energie Atomique, IRAMIS, Service interdisciplinaire sur les systèmes moléculaires et matériaux, CEA/CNRS UMR 3299, 91191, Gif-sur-Yvette (France)

    2016-01-22

    Theoretical approaches are useful and powerful tools for more accurate and efficient spin dynamics simulation to understand experiments and devising new RF pulse sequence in nuclear magnetic resonance. Solid-state NMR is definitely a timely topic or area of research, and not many papers on the respective theories are available in the literature of nuclear magnetic resonance or physics reports. This report presents the power and the salient features of the promising theoretical approach called Floquet–Magnus expansion that is helpful to describe the time evolution of the spin system at all times in nuclear magnetic resonance. The report presents a broad view of algorithms of spin dynamics, based on promising and useful theory of Floquet–Magnus expansion. This theory provides procedures to control and describe the spin dynamics in solid-state NMR. Major applications of the Floquet–Magnus expansion are illustrated by simple solid-state NMR and physical applications such as in nuclear, atomic, molecular physics, and quantum mechanics, NMR, quantum field theory and high energy physics, electromagnetism, optics, general relativity, search of periodic orbits, and geometric control of mechanical systems. The aim of this report is to bring to the attention of the spin dynamics community, the bridge that exists between solid-state NMR and other related fields of physics and applied mathematics. This review article also discusses future potential theoretical directions in solid-state NMR.

  18. Force-detected nuclear magnetic resonance: recent advances and future challenges.

    Science.gov (United States)

    Poggio, M; Degen, C L

    2010-08-27

    We review recent efforts to detect small numbers of nuclear spins using magnetic resonance force microscopy. Magnetic resonance force microscopy (MRFM) is a scanning probe technique that relies on the mechanical measurement of the weak magnetic force between a microscopic magnet and the magnetic moments in a sample. Spurred by the recent progress in fabricating ultrasensitive force detectors, MRFM has rapidly improved its capability over the last decade. Today it boasts a spin sensitivity that surpasses conventional, inductive nuclear magnetic resonance detectors by about eight orders of magnitude. In this review we touch on the origins of this technique and focus on its recent application to nanoscale nuclear spin ensembles, in particular on the imaging of nanoscale objects with a three-dimensional (3D) spatial resolution better than 10 nm. We consider the experimental advances driving this work and highlight the underlying physical principles and limitations of the method. Finally, we discuss the challenges that must be met in order to advance the technique towards single nuclear spin sensitivity-and perhaps-to 3D microscopy of molecules with atomic resolution.

  19. On the Fer expansion: Applications in solid-state nuclear magnetic resonance and physics

    International Nuclear Information System (INIS)

    Mananga, Eugene Stephane

    2016-01-01

    Theoretical approaches are useful and powerful tools for more accurate and efficient spin dynamics simulation to understand experiments and devising new RF pulse sequence in nuclear magnetic resonance. Solid-state NMR is definitely a timely topic or area of research, and not many papers on the respective theories are available in the literature of nuclear magnetic resonance or physics reports. This report presents the power and the salient features of the promising theoretical approach called Fer expansion that is helpful to describe the evolution of the spin system in nuclear magnetic resonance. The report presents a broad view of algorithms of spin dynamics based on the Fer expansion which provides procedures to control and describe the spin dynamics in solid-state NMR. Significant applications of the Fer expansion are illustrated in NMR and in physics such as classical physics, nonlinear dynamics systems, celestial mechanics and dynamical astronomy, hydrodynamics, nuclear, atomic, molecular physics, and quantum mechanics, quantum field theory, high energy physics, electromagnetism. The aim of this report is to bring to the attention of the spin dynamics community, the bridge that exists between solid-state NMR and other related fields of physics and applied mathematics.

  20. 43. Polish Seminar on Nuclear Magnetic Resonance and its Applications. Cracow. Abstracts

    International Nuclear Information System (INIS)

    2010-12-01

    42 Polish Seminar on Nuclear Magnetic Resonance and its Applications, held on 1-2 December 2010 in Cracow (Poland), was devoted to the development of different magnetic resonance techniques and application of such techniques as crucial part of the studies. The Report contains 58 short descriptions of the contributions submitted by the participants of the Seminar. They cover all areas of the NMR application in major branches of basic chemistry, structural biology, medicine and materials science. Also recent results of the quantum chemical calculations of the NMR parameters are presented.

  1. Giant dipole resonances in hot nuclear matter in the model of self-relaxing mean field

    International Nuclear Information System (INIS)

    Okolowicz, J.; Ploszajczak, M.; Drozdz, S.; Caurier, E.

    1989-01-01

    The extended time-dependent Hartree-Fock approach is applied for the description of the isovector giant dipole resonance in 40 Ca at finite temperatures. The thermalization process is described using the relaxation-time ansatz for the collision integral. Strong inhibition of the giant-dipole-resonance γ-decay is found due to the fast vaporization of the nuclear surface for thermal excitation energies above E * /A ≅ 4.5 MeV. This pre-equilibrium emission of particles in the vapor phase is associated with the radial expansion of nucleus and with the vanishing particle binding energies mainly for protons. (orig.)

  2. Mirror and Bragg reflections of neutrons at a nuclear resonance: [Final technical report

    International Nuclear Information System (INIS)

    Batigun, C.M.; Brugger, R.M.

    1987-01-01

    These experiments have observed the mirror reflection and Bragg diffraction of neutrons at the energy of a low lying nuclear resonance of 115 In. The reflector was a mirror of In metal with the resonance at 1.457 eV. The mirror reflection for different angles of incidence has been measured and sets of data showing the relative reflectivities have been obtained. For the Bragg diffraction, the crystal was a wafer of InP and several examples of Bragg reflections near 1.455 eV were measured. 4 refs., 12 figs

  3. Sum rule approach to the study of statistical decay properties of nuclear giant resonances

    International Nuclear Information System (INIS)

    Adhikari, S.K.; Hussein, M.S.

    1987-03-01

    Corrections to the well-known statistical sum rule that relates the summed transmission coefficients on the one hand and 2πΓ C.N. .ρ C.N. On the other, in the context of the statistical decay properties of nuclear giant resonances, are discussed. These corrections arise both from pre-equilibrium processes as well as from the giant resonance itself. It is shown that the compound nucleus average width is reduced as a result of these corrections. (Author) [pt

  4. The Co59 nuclear magnetic resonances in (Ysub(1-x)Gdsub(x))2Co17

    International Nuclear Information System (INIS)

    Nagai, Hiroyuki; Yoshie, Hiroshi; Unate, Takao; Tsujimura, Akira; Deportes, J.

    1976-01-01

    The nuclear magnetic resonances of Co 59 in (Ysub(1-x)Gdsub(x)) 2 Co 17 have been observed at 77 K as a function of x (0 2 Co 17 and Gd 2 Co 17 is at most 7 kOe in magnitude, which is comparable to that obtained in GdCo 5 . The sign of the obtained difference depends on the Co sites. The difference is qualitatively explained as the contribution of 4f electrons of Gd atoms to the hyperfine field. The temperature dependence of the resonance frequencies in Gd 2 Co 17 has also been measured. (auth.)

  5. Effect of nonlinearity of spin interaction with electromagnetic resonance field on characteristics of polarized nuclear target

    International Nuclear Information System (INIS)

    Vertij, A.A.; Gavrilov, S.P.; Shestopalov, V.P.

    1990-01-01

    Interaction of incident nuclear particle beam with J = 1/2 (neutrons) spin and (J = 1/2) protons with the target substance is considered. It is shown that neutron polarization at the target exit and neutron transparency (G) of the target depend significantly on incident wave amplitude level and physical parameter values which characterize the target, such as target temperature, resonator mirror reflection factor, number of spins interacting with the field, etc. Under interaction of neutrons with a target resonator which features a high mirror reflection factor and low losses for absorption which is not related to magnetic dipole absorption, a bistable response of neutron polarization and G manifests itself. 1 ref

  6. Nuclear magnetic resonance in low-symmetry superconductors

    Science.gov (United States)

    Cavanagh, D. C.; Powell, B. J.

    2018-01-01

    We consider the nuclear spin-lattice relaxation rate 1 /T1 in superconductors with accidental nodes, i.e., zeros of the order parameter that are not enforced by its symmetries. Such nodes in the superconducting gap are not constrained by symmetry to a particular position on the Fermi surface. We show, analytically and numerically, that a Hebel-Slichter-like peak occurs even in the absence of an isotropic component of the superconducting gap. For a gap with symmetry-required nodes the Fermi velocity at the node must point along the node. For accidental nodes this is not, in general, the case. This leads to additional terms in spectral function and hence the density of states. These terms lead to a logarithmic divergence in 1 /T1T at T →Tc- in models neglecting disorder and interactions [except for those leading to superconductivity; here T is temperature, Tc-=limδ→0(Tc-δ ) , and Tc is the critical temperature]. This contrasts with the usual Hebel-Slichter peak which arises from the coherence factors due to the isotropic component of the gap and leads to a divergence in 1 /T1T somewhat below Tc. The divergence in superconductors with accidental nodes is controlled by either disorder or additional electron-electron interactions. However, for reasonable parameters, neither of these effects removes the peak altogether. This provides a simple experimental method to distinguish between symmetry-required and accidental nodes.

  7. Ring resonator systems to perform optical communication enhancement using soliton

    CERN Document Server

    Amiri, Iraj Sadegh

    2014-01-01

    The title explain new technique of secured and high capacity optical communication signals generation by using the micro and nano ring resonators. The pulses are known as soliton pulses which are more secured due to having the properties of chaotic and dark soliton signals with ultra short bandwidth. They have high capacity due to the fact that ring resonators are able to generate pulses in the form of solitons in multiples and train form. These pulses generated by ring resonators are suitable in optical communication due to use the compact and integrated rings system, easy to control, flexibi

  8. Spin-locking of half-integer quadrupolar nuclei in nuclear magnetic resonance of solids: second-order quadrupolar and resonance offset effects.

    Science.gov (United States)

    Ashbrook, Sharon E; Wimperis, Stephen

    2009-11-21

    Spin-locking of spin I=3/2 and I=5/2 nuclei in the presence of small resonance offset and second-order quadrupolar interactions has been investigated using both exact and approximate theoretical and experimental nuclear magnetic resonance (NMR) approaches. In the presence of second-order quadrupolar interactions, we show that the initial rapid dephasing that arises from the noncommutation of the state prepared by the first pulse and the spin-locking Hamiltonian gives rise to tensor components of the spin density matrix that are antisymmetric with respect to inversion, in addition to those symmetric with respect to inversion that are found when only a first-order quadrupolar interaction is considered. We also find that spin-locking of multiple-quantum coherence in a static solid is much more sensitive to resonance offset than that of single-quantum coherence and show that good spin-locking of multiple-quantum coherence can still be achieved if the resonance offset matches the second-order shift of the multiple-quantum coherence in the appropriate reference frame. Under magic angle spinning (MAS) conditions, and in the "adiabatic" limit, we demonstrate that rotor-driven interconversion of central-transition single- and three-quantum coherences for a spin I=3/2 nucleus can be best achieved by performing the spin-locking on resonance with the three-quantum coherence in the three-quantum frame. Finally, in the "sudden" MAS limit, we show that spin I=3/2 spin-locking behavior is generally similar to that found in static solids, except when the central-transition nutation rate matches a multiple of the MAS rate and a variety of rotary resonance phenomena are observed depending on the internal spin interactions present. This investigation should aid in the application of spin-locking techniques to multiple-quantum NMR of quadrupolar nuclei and of cross-polarization and homonuclear dipolar recoupling experiments to quadrupolar nuclei such as (7)Li, (11)B, (17)O, (23)Na, and

  9. Scientific opportunities in nuclear resonance spectroscopy from source-driven revolution

    Energy Technology Data Exchange (ETDEWEB)

    Shenoy, G. K., E-mail: gks@aps.anl.gov [Argonne National Laboratory (United States); Roehlsberger, R. [Deutsches Elektronen Synchrotron, DESY (Germany)

    2008-02-15

    From the beginning of its discovery the Moessbauer effect has continued to be one of the most powerful tools with broad applications in diverse areas of science and technology. With the advent of synchrotron radiation sources such as the Advanced Photon Source (APS), the European Synchrotron Radiation Facility (ESRF) and the Super Photon Ring-8 (SPring-8), the tool has enlarged its scope and delivered new capabilities. The popular techniques most generally used in the field of materials physics, chemical physics, geoscience, and biology are hyperfine spectroscopy via elastic nuclear forward scattering (NFS), vibrational spectroscopy via nuclear inelastic scattering (NRIXS), and, to a lesser extent, diffusional dynamics from quasielastic nuclear forward scattering (QNFS). As we look ahead, new storage rings with enhanced brilliance such as PETRA-III under construction at DESY, Hamburg, and PEP-III in its early design stage at SLAC, Stanford, will provide new and unique science opportunities. In the next two decades, x-ray free-electron lasers (XFELs), based both on self-amplified spontaneous emission (SASE-XFELs) and a seed (SXFELs), with unique time structure, coherence and a five to six orders higher average brilliance will truly revolutionize nuclear resonance applications in a major way. This overview is intended to briefly address the unique radiation characteristics of new sources on the horizon and to provide a glimpse of scientific prospects and dreams in the nuclear resonance field from the new radiation sources. We anticipate an expanded nuclear resonance research activity with applications such as spin and phonon mapping of a single nanostructure and their assemblies, interfaces, and surfaces; spin dynamics; nonequilibrium dynamics; photochemical reactions; excited-state spectroscopy; and nonlinear phenomena.

  10. Two-phase flow characterisation by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Leblond, J.; Javelot, S.; Lebrun, D.; Lebon, L.

    1998-01-01

    The results presented in this paper demonstrate the performance of the PFGSE-NMR to obtain a complete characterisation of two-phase flows. Different methods are proposed to characterise air-water flows in different regimes: stationary two-phase flows and flows in transient condition. Finally a modified PFGSE is proposed to analyse the turbulence of air-water bubbly flow. (author)

  11. Determination of scutellarin in breviscapine preparations using quantitative proton nuclear magnetic resonance spectroscopy

    Directory of Open Access Journals (Sweden)

    Zhenzuo Jiang

    2016-04-01

    Full Text Available The objective of the present study was to develop the selection criteria of proton signals for the determination of scutellarin using quantitative nuclear magnetic resonance (qNMR, which is the main bioactive compound in breviscapine preparations for the treatment of cerebrovascular disease. The methyl singlet signal of 3-(trimethylsilylpropionic-2,2,3,3-d4 acid sodium salt was selected as the internal standard for quantification. The molar concentration of scutellarin was determined by employing different proton signals. To obtain optimum proton signals for the quantification, different combinations of proton signals were investigated according to two selection criteria: the recovery rate of qNMR method and quantitative results compared with those obtained with ultra-performance liquid chromatography. As a result, the chemical shift of H-2′ and H-6′ at δ 7.88 was demonstrated as the most suitable signal with excellent linearity range, precision, and recovery for determining scutellarin in breviscapine preparations from different manufacturers, batch numbers, and dosage forms. Hierarchical cluster analysis was employed to evaluate the determination results. The results demonstrated that the selection criteria of proton signals established in this work were reliable for the qNMR study of scutellarin in breviscapine preparations.

  12. Applied nuclear γ-resonance as fingerprint technique in geochemistry and mineralogy

    International Nuclear Information System (INIS)

    Constantinescu, S.

    2003-01-01

    The aim of the present paper is to evidence the new developments of one of the most refined technique, the nuclear γ resonance or the well-known Moessbauer effect, in the field of mineralogical and geo-chemical investigation. There are many Moessbauer studies on minerals, but the development, the new performance of the Moessbauer equipment and of the computers impose to review more profoundly and more thoroughly the information, which this non-destructive technique offers. This task became more and more pressingly because a lot of minerals contain in high proportion, the Moessbauer isotopes. Generally, the mineralogists, physicists and chemists hope to obtain more refined and complete information about the physics and chemistry synthesis aspects in solid state transformation of some natural and synthetic materials and also about the structural aspects, by these kind of techniques. On this line, the authors very shortly review the principal aspects of the Moessbauer spectroscopy and underline the most important information one can obtain from spectra. The recent results, which have been obtained on minerals extracted from Romanian geological deposits by the authors, will be discussed in detail in the second part of this article. (authors)

  13. (14) N nuclear quadrupole resonance study of piroxicam: confirmation of new polymorphic form V.

    Science.gov (United States)

    Lavrič, Zoran; Pirnat, Janez; Lužnik, Janko; Puc, Uroš; Trontelj, Zvonko; Srčič, Stane

    2015-06-01

    A new polymorphic crystal form of piroxicam was discovered while preparing crystalline samples of piroxicam for (14) N nuclear quadrupole resonance (NQR) analysis. The new crystal form, designated as V, was prepared by evaporative recrystallization from dichloromethane. Three known polymorphic forms (I, II, and III) were also prepared. Our aim was to apply (14) N NQR to characterize the new polymorphic form of piroxicam and compare the results with those of the other known polymorphic forms. Additional analytical methods used for characterization were X-ray powder diffraction (XRPD), thermal analysis, and vibrational spectroscopy. For the first time, a complete set of nine characteristic (14) N NQR frequencies was found for each prepared polymorph of piroxicam. The consistent set of measured frequencies and calculated characteristic quadrupole parameters found for the new polymorphic form V is a convincing evidence that we are dealing with a new form. The already known piroxicam polymorphic forms were characterized similarly. The XRPD results were in accordance with the conclusions of (14) N NQR analysis. The performed study clearly demonstrates a strong potential of (14) N NQR method to be applied as a highly discriminative spectroscopic analytical tool to characterize polymorphic forms. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  14. Nuclear magnetic resonance-based serum metabolic profiling of dairy cows with footrot.

    Science.gov (United States)

    Zheng, Jiasan; Sun, Lingwei; Shu, Shi; Zhu, Kuiling; Xu, Chuang; Wang, Junsong; Wang, Hongbin

    2016-10-01

    Footrot is a debilitating and contagious disease in dairy cows, caused by the Gram-negative anaerobe Dichelobacter nodosus. 1 H-NMR (nuclear magnetic resonance)-based metabolomics has been previously used to understand the pathology and etiology of several diseases. The objective of this study was to characterize serum from dairy cows with footrot (n=10) using 1 H-NMR-based metabolomics and chemometric analyses. 1 H-NMR spectroscopy with multivariate pattern recognition (principal component analysis and orthogonal partial least-squares discriminant analysis) was performed to identify biomarkers in cows with footrot (F) and healthy controls (C). 1 H-NMR analysis facilitated the identification of 21 metabolites. Among these metabolites, 4 metabolites were higher and 17 metabolites were lower in the F group than in the C group. The serum levels of 5 metabolites were significantly different (Pcows with footrot have altered carbohydrate, amino acid, lipid and energy metabolic pathways. Metabolomic approaches are a clinically useful diagnostic tool for understanding the biochemical alterations and mechanisms of several diseases.

  15. Experimental aspect of solid-state nuclear magnetic resonance studies of biomaterials such as bones.

    Science.gov (United States)

    Singh, Chandan; Rai, Ratan Kumar; Sinha, Neeraj

    2013-01-01

    Solid-state nuclear magnetic resonance (SSNMR) spectroscopy is increasingly becoming a popular technique to probe micro-structural details of biomaterial such as bone with pico-meter resolution. Due to high-resolution structural details probed by SSNMR methods, handling of bone samples and experimental protocol are very crucial aspects of study. We present here first report of the effect of various experimental protocols and handling methods of bone samples on measured SSNMR parameters. Various popular SSNMR experiments were performed on intact cortical bone sample collected from fresh animal, immediately after removal from animal systems, and results were compared with bone samples preserved in different conditions. We find that the best experimental conditions for SSNMR parameters of bones correspond to preservation at -20 °C and in 70% ethanol solution. Various other SSNMR parameters were compared corresponding to different experimental conditions. Our study has helped in finding best experimental protocol for SSNMR studies of bone. This study will be of further help in the application of SSNMR studies on large bone disease related animal model systems for statistically significant results. © 2013 Elsevier Inc. All rights reserved.

  16. A reactor for high-throughput high-pressure nuclear magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Beach, N. J.; Knapp, S. M. M.; Landis, C. R., E-mail: landis@chem.wisc.edu [Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53719 (United States)

    2015-10-15

    The design of a reactor for operando nuclear magnetic resonance (NMR) monitoring of high-pressure gas-liquid reactions is described. The Wisconsin High Pressure NMR Reactor (WiHP-NMRR) design comprises four modules: a sapphire NMR tube with titanium tube holder rated for pressures as high as 1000 psig (68 atm) and temperatures ranging from −90 to 90 °C, a gas circulation system that maintains equilibrium concentrations of dissolved gases during gas-consuming or gas-releasing reactions, a liquid injection apparatus that is capable of adding measured amounts of solutions to the reactor under high pressure conditions, and a rapid wash system that enables the reactor to be cleaned without removal from the NMR instrument. The WiHP-NMRR is compatible with commercial 10 mm NMR probes. Reactions performed in the WiHP-NMRR yield high quality, information-rich, and multinuclear NMR data over the entire reaction time course with rapid experimental turnaround.

  17. Phosphorus-31 NMR (nuclear magnetic resonance) analysis of gold plating baths

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.E.

    1990-01-01

    This report describes the nuclear magnetic resonance (NMR) analysis of the gold plating baths in the Micro-Miniature Electronic Assembly department of Allied-Signal Inc., Kansas City Division (KCD). The baths were analyzed for phosphorylated components. In freshly prepared gold plating baths, a 50-percent aqueous solution of aminotrimethylphosphonate (ATMP) is the principal compound observed. As the bath is used in production, the ATMP breaks down and new materials (phosphate, ADMP, and AMMP) are identified. The NMR method was used to monitor the concentrations of the ATMP and breakdown products for a nine-month period. The 225-liter bath had plated approximately 100 square feet of gold during the nine-month period. These results can be used to predict the performance of baths as they are used in production. The accuracy of the analysis is 96 percent for ATMP and 92 percent for phosphate. The precision (relative standard deviation) is 5.2 percent for ATMP and 4.5 percent for phosphate. 1 ref., 5 figs., 2 tabs.

  18. Study on VCSEL laser heating chip in nuclear magnetic resonance gyroscope

    Science.gov (United States)

    Liang, Xiaoyang; Zhou, Binquan; Wu, Wenfeng; Jia, Yuchen; Wang, Jing

    2017-10-01

    In recent years, atomic gyroscope has become an important direction of inertial navigation. Nuclear magnetic resonance gyroscope has a stronger advantage in the miniaturization of the size. In atomic gyroscope, the lasers are indispensable devices which has an important effect on the improvement of the gyroscope performance. The frequency stability of the VCSEL lasers requires high precision control of temperature. However, the heating current of the laser will definitely bring in the magnetic field, and the sensitive device, alkali vapor cell, is very sensitive to the magnetic field, so that the metal pattern of the heating chip should be designed ingeniously to eliminate the magnetic field introduced by the heating current. In this paper, a heating chip was fabricated by MEMS process, i.e. depositing platinum on semiconductor substrates. Platinum has long been considered as a good resistance material used for measuring temperature The VCSEL laser chip is fixed in the center of the heating chip. The thermometer resistor measures the temperature of the heating chip, which can be considered as the same temperature of the VCSEL laser chip, by turning the temperature signal into voltage signal. The FPGA chip is used as a micro controller, and combined with PID control algorithm constitute a closed loop control circuit. The voltage applied to the heating resistor wire is modified to achieve the temperature control of the VCSEL laser. In this way, the laser frequency can be controlled stably and easily. Ultimately, the temperature stability can be achieved better than 100mK.

  19. Metabolomics with Nuclear Magnetic Resonance Spectroscopy in a Drosophila melanogaster Model of Surviving Sepsis

    Science.gov (United States)

    Bakalov, Veli; Amathieu, Roland; Triba, Mohamed N.; Clément, Marie-Jeanne; Reyes Uribe, Laura; Le Moyec, Laurence; Kaynar, Ata Murat

    2016-01-01

    Patients surviving sepsis demonstrate sustained inflammation, which has been associated with long-term complications. One of the main mechanisms behind sustained inflammation is a metabolic switch in parenchymal and immune cells, thus understanding metabolic alterations after sepsis may provide important insights to the pathophysiology of sepsis recovery. In this study, we explored metabolomics in a novel Drosophila melanogaster model of surviving sepsis using Nuclear Magnetic Resonance (NMR), to determine metabolite profiles. We used a model of percutaneous infection in Drosophila melanogaster to mimic sepsis. We had three experimental groups: sepsis survivors (infected with Staphylococcus aureus and treated with oral linezolid), sham (pricked with an aseptic needle), and unmanipulated (positive control). We performed metabolic measurements seven days after sepsis. We then implemented metabolites detected in NMR spectra into the MetExplore web server in order to identify the metabolic pathway alterations in sepsis surviving Drosophila. Our NMR metabolomic approach in a Drosophila model of recovery from sepsis clearly distinguished between all three groups and showed two different metabolomic signatures of inflammation. Sham flies had decreased levels of maltose, alanine, and glutamine, while their level of choline was increased. Sepsis survivors had a metabolic signature characterized by decreased glucose, maltose, tyrosine, beta-alanine, acetate, glutamine, and succinate. PMID:28009836

  20. Nuclear performance optimization of the Be/Li/Th blanket for the fusion breeder

    International Nuclear Information System (INIS)

    Lee, J.D.; Bandini, B.R.

    1985-01-01

    More rigorous nuclear analysis, including treatment of resonance self-shielding effects coupled with an optimization procedure, has resulted in improved performance of the Be/Li/Th blanket. Net U-233 breeding ratio has increased 36% (to 0.84) while at an average U-233/Th ratio of 0.5 a/o average energy multiplication has increased only 12% (to 2.1) compared with earlier results

  1. Electric field gradient in FeTiO3 by nuclear magnetic resonance and ab initio calculations.

    Science.gov (United States)

    Procházka, V; Stěpánková, H; Chlan, V; Tuček, J; Cuda, J; Kouřil, K; Filip, J; Zbořil, R

    2011-05-25

    Temperature dependence of nuclear magnetic resonance (NMR) spectra of (47)Ti and (49)Ti in polycrystalline ilmenite FeTiO(3) was measured in the range from 5 to 300 K under an external magnetic field of 9.401 T. NMR spectra collected between 300 and 77 K exhibit a resolved quadrupole splitting. The electric field gradient (EFG) tensor was evaluated for Ti nuclei and the ratio of (47)Ti and (49)Ti nuclear quadrupole moments was refined during the fitting procedure. Below 77 K, the fine structure of quadrupole splitting disappears due to the enormous increase of anisotropy. As a counterpart, ab initio calculations were performed using full potential augmented plane waves + local orbitals. The calculated EFG tensors for Ti and Fe were compared to the experimental ones evaluated from NMR and the Mössbauer spectroscopy experiments.

  2. Nuclear resonance absorption (NRA): method and application to detection of contraband in a baggage, cargo and vehicles

    International Nuclear Information System (INIS)

    Goldenberg, M.B.; Vartsky, D.; Engler, G.

    1996-01-01

    Nuclear Resonance Absorption (NRA) has played a prominent role in nuclear spectroscopy for almost 5 decades, but found only few and marginal applications outside the laboratory before 1985. In that year the situation changed markedly when scientists from this laboratory proposed to the Federal Aviation Administration (FAA) in the U.S. to study its suitability for detecting explosives in passenger baggage via nitrogen-specific radiographic imaging (explosives, as a category, have inordinately high nitrogen densities). Following a basic feasibility study and the first laboratory demonstration of explosives detection in 1989, this project has attained the stage of a pre-industrial prototype that exhibited excellent performance characteristics in a 1993 blind test conducted by the FAA. In terms of NRA operational system concept, data taking methodology, development of dedicated detectors and image analysis algorithms, the Soreq group has made a major, if not exclusive, contribution over the years. (authors)

  3. /sup 31/P nuclear-magnetic-resonance studies an the developing embryos of Xenopus laevis

    Energy Technology Data Exchange (ETDEWEB)

    Gadian, D G [Oxford Univ. (UK). Dept. of Biochemistry; Colman, A [Oxford Univ. (UK). Dept. of Zoology

    1976-01-01

    The concentrations of nucleoside triphosphate, inorganic phosphate and yolk proteins, phosvitin and lipovitellin, have been monitored in living embryos of Xenopus laevis by /sup 31/P nuclear magnetic resonance (NMR) spectroscopy. The nucleoside triphosphate levels remain relatively constant at about 3.5 - 4.5 nmol/embryo at least until the 'spontaneous movement' stage of development. By the swimming tadpole stage an inorganic phosphate resonance representing about 30 nmol/embryo becomes evident in the NMR spectrum. Computer manipulation also shows such a resonance, although smaller, to be present at a somewhat earlier developmental stage; these findings are confirmed biochemically. The major contribution to the NMR spectrum of oocytes, unfertilized eggs and early embryos is the yolk phosphoprotein resonance. On isolation of the yolk from the embryos it is possible to quantify the contribution to the NMR spectrum from the lipid-phosphate and protein-phosphate moieties of the yolk proteins. During development, as the yolk is used up, it is found that the protein-phosphate resonance disappears at a greater rate than the lipid-phosphate peak. The total phosphorus content of the embryo (ca. 200 nmol/embryo) is shown biochemically to remain constant during development; however, the total amount of phosphorus observed by NMR decreases by about 40% during development. From the resonance positions of their ..cap alpha.., ..beta.. and ..gamma.. phosphate groups is is deduced that the nucleoside triphosphate molecules are liganded in vivo to a divalent cation which is not manganese, but could be either magnesium or calcium. From the position of the inorganic phosphate resonance it is deduced that the internal pH of embryos where this resonance is evident is 6.8 +- 0.2.

  4. Measurement of changes in nuclear charge radii of 2r by laser-induced resonance fluorescence

    International Nuclear Information System (INIS)

    Gangrskij, Yu.P.; Zemlyanoj, S.G.; Marinova, K.P.; Markov, B.N.; Khoang Tkhi Kim Khueh; Chan Kong Tam; Kul'dzhanov, B.K.

    1987-01-01

    The optical isotopic shifts of Zr stable isotopes have been measured in three atomic transitions of type 4d 2 5s 2 → 4d 2 5s5p using the technique of laser-induced resonance fluorescence. The changes of nuclear mean-square charge radius Δ 2 > have been determined. The extracted values of Δ 2 > are compared to predictions of the droplet model. It is shown that the droplet model calculations can be made to agree with the experimental results, if changes of nuclear dynamical octupole deformation and of surface diffuseness parameter are taken into account

  5. Investigation of Condensed Media in Weak Fields by the Method of Nuclear Magnetic Resonance

    Science.gov (United States)

    Davydov, V. V.; Myazin, N. S.; Dudkin, V. I.; Velichko, E. N.

    2018-05-01

    A compact design of a rapid-response nuclear magnetic spectrometer for investigation of condensed media in weak fields is reported. As a result of investigation of different condensed media, special features of recording a nuclear magnetic resonance (NMR) signal in a weak magnetic field from a small volume of the medium under study are established. For the first time the NMR absorption spectra of condensed media in a weak field are collected. Based on the results of experimental studies, the potential of using a compact NMR-spectrometer for condensed media monitoring in a rapid response mode is determined.

  6. Nuclear structure studies on medium-heavy mass nuclei using the method of nuclear resonance fluorescence; Kernstrukturuntersuchungen in mittelschweren Atomkernen mit der Methode der Kernresonanzfluoreszenz

    Energy Technology Data Exchange (ETDEWEB)

    Zweidinger, Markus

    2016-06-22

    In the present work the dipole strength distribution in the stable even-even isotopes {sup 92}Zr and {sup 94}Zr is investigated. To excite the nuclei from the ground state to an excited state, real photons are used. This method is called Nuclear Resonance Fluorescence. The measurements were performed at two different setups. The first one is the Darmstadt High Intensity Photon Setup (DHIPS). At DHIPS the measurements yield information about the spin quantum number and the integrated cross section. The second part of the experiments took place at the High Intensity γ-ray Source (HIγS). Here, information about the parity quantum number and the averaged branching ratio of the excited state is accessible. In total, 105 dipole excited states in the nucleus {sup 92}Zr and 124 in the isotope {sup 94}Zr are observed, most of them for the first time. The extracted dipole strength distribution is investigated for the existence of the pygmy dipole resonance that was observed in neighboring nuclei. Furthermore, in previously performed experiments on the isotope {sup 90}Zr, the spin-flip M1 resonance was observed as well. Therefore, also the magnetic dipole strength is investigated. Further, by comparison with global systematics, the two-phonon state is identified. Additionally, the averaged branching ratio is compared to the results of theoretical calculations in the framework of the statistical model.

  7. Billion-Fold Enhancement in Sensitivity of Nuclear Magnetic Resonance Spectroscopy for Magnesium Ions in Solution

    CERN Document Server

    Gottberg, Alexander; Kowalska, Magdalena; Bissell, Mark L; Arcisauskaite, Vaida; Blaum, Klaus; Helmke, Alexander; Johnston, Karl; Kreim, Kim; Larsen, Flemming H; Neugart, Rainer; Neyens, Gerda; Garcia Ruiz, Ronald F; Szunyogh, Daniel; Thulstrup, Peter W; Yordanov, Deyan T; Hemmingsen, Lars

    2014-01-01

    β-nuclear magnetic resonance (NMR) spectroscopy is highly sensitive compared to conventional NMR spectroscopy, and may be applied for several elements across the periodic table. β-NMR has previously been successfully applied in the fields of nuclear and solid-state physics. In this work, β-NMR is applied, for the first time, to record an NMR spectrum for a species in solution. 31Mg β-NMR spectra are measured for as few as 107 magnesium ions in ionic liquid (EMIM-Ac) within minutes, as a prototypical test case. Resonances are observed at 3882.9 and 3887.2 kHz in an external field of 0.3 T. The key achievement of the current work is to demonstrate that β-NMR is applicable for the analysis of species in solution, and thus represents a novel spectroscopic technique for use in general chemistry and potentially in biochemistry.

  8. Methylmalonic aciduria and propionic acidaemia studied by proton nuclear magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Iles, R A; Hind, A J; Chalmers, R A

    1986-12-15

    Proton nuclear magnetic resonance spectroscopy has been used to monitor changes in urinary metabolites in a patient with propionic acidaemia over a period of 10 months and in a patient with methylmalonic aciduria over a period of 11 days. Results could be obtained within 5-10 min of sample receipt. In the spectra on the patient with propionic acidaemia not only could fluctuations in 3-hydroxypropionate and propionylglycine excretion be followed, but also variations in creatine, glycine and betaine, which were often present at millimolar concentrations. The patient with methylmalonic aciduria had an acute episode of severe ketoacidosis during which the glycine excretion fell but creatine excretion rose and then fell on recovery from the episode. The changes in the creatine excretion may reflect disorders in intracellular energy supply. Nuclear magnetic resonance is a powerful technique for monitoring metabolic perturbations in the organic acidurias in 'real-time', allowing the planning and evaluation of therapy. (Auth.). 18 refs.; 4 figs.; 3 tabs.

  9. Evaluation of poly(vinylpyrrolidone) and collagen by Low Field Nuclear Magnetic Resonance Spectroscopy

    International Nuclear Information System (INIS)

    Costa, Paula de M.; Tavares, Maria I.B.

    2005-01-01

    Blends of natural and synthetic polymers represent a new class of materials with better mechanical properties and biocompatibility than those of the single components. Collagen and poly(vinylpyrrolidone) are well known for their important biological properties. The blending of collagen with poly(vinylpyrrolidone) makes it possible to obtain new materials in which strong interactions between the synthetic and biological components occur. Do to the excellent biocompatibility of these polymers, this blend has been much studied intending biomedical applications. And a one technique that can provide important information on molecular mobility, compatibility and even evaluate the interactions that can occur with these polymers is the Low Field Nuclear Magnetic Resonance Spectroscopy. Thus, the purpose of this work is to evaluate collagen and poly(vinylpyrrolidone) by Low Field Nuclear Magnetic Resonance Spectroscopy. From the values of relaxation times obtained, we can conclude that these materials have different interactions, and different mobility domains, confirming the heterogeneity and complexity of these materials. (author)

  10. Methylmalonic aciduria and propionic acidaemia studied by proton nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Iles, R.A.; Hind, A.J.; Chalmers, R.A.

    1986-01-01

    Proton nuclear magnetic resonance spectroscopy has been used to monitor changes in urinary metabolites in a patient with propionic acidaemia over a period of 10 months and in a patient with methylmalonic aciduria over a period of 11 days. Results could be obtained within 5-10 min of sample receipt. In the spectra on the patient with propionic acidaemia not only could fluctuations in 3-hydroxypropionate and propionylglycine excretion be followed, but also variations in creatine, glycine and betaine, which were often present at millimolar concentrations. The patient with methylmalonic aciduria had an acute episode of severe ketoacidosis during which the glycine excretion fell but creatine excretion rose and then fell on recovery from the episode. The changes in the creatine excretion may reflect disorders in intracellular energy supply. Nuclear magnetic resonance is a powerful technique for monitoring metabolic perturbations in the organic acidurias in 'real-time', allowing the planning and evaluation of therapy. (Auth.)

  11. Dephasing due to Nuclear Spins in Large-Amplitude Electric Dipole Spin Resonance.

    Science.gov (United States)

    Chesi, Stefano; Yang, Li-Ping; Loss, Daniel

    2016-02-12

    We analyze effects of the hyperfine interaction on electric dipole spin resonance when the amplitude of the quantum-dot motion becomes comparable or larger than the quantum dot's size. Away from the well-known small-drive regime, the important role played by transverse nuclear fluctuations leads to a Gaussian decay with characteristic dependence on drive strength and detuning. A characterization of spin-flip gate fidelity, in the presence of such additional drive-dependent dephasing, shows that vanishingly small errors can still be achieved at sufficiently large amplitudes. Based on our theory, we analyze recent electric dipole spin resonance experiments relying on spin-orbit interactions or the slanting field of a micromagnet. We find that such experiments are already in a regime with significant effects of transverse nuclear fluctuations and the form of decay of the Rabi oscillations can be reproduced well by our theory.

  12. Proton nuclear magnetic resonance in paramagnetic CoCl2.6H2O

    International Nuclear Information System (INIS)

    Oravcova, J.; Murin, J.; Rakos, M.; Olcak, D.

    1978-01-01

    Nuclear magnetic resonance (NMR) is studied of protons of the crystal water of paramagnetic CoCl 2 .6H 2 O. The measurements were carried out on powdered samples at room temperature, for values of the external magnetic field ranging from 0.3 to 1.0 T. The NMR signals of protons of the crystal water exhibit asymmetric shape which changes with the applied external magnetic field. We found that the second moment of the resonance line shows a linear dependence on the square of the induction of the externally applied magnetic field. The cause of the asymmetry of the NMR line of protons of the crystal water and the dependence of the second moment of the resonance line on the induction of external magnetic field are interpreted. (author)

  13. Solid-state nuclear-spin quantum computer based on magnetic resonance force microscopy

    International Nuclear Information System (INIS)

    Berman, G. P.; Doolen, G. D.; Hammel, P. C.; Tsifrinovich, V. I.

    2000-01-01

    We propose a nuclear-spin quantum computer based on magnetic resonance force microscopy (MRFM). It is shown that an MRFM single-electron spin measurement provides three essential requirements for quantum computation in solids: (a) preparation of the ground state, (b) one- and two-qubit quantum logic gates, and (c) a measurement of the final state. The proposed quantum computer can operate at temperatures up to 1 K. (c) 2000 The American Physical Society

  14. S100 lathe bed pulse generator applied to pulsed nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Cernicchiaro, G.R.C.; Rudge, M.G.; Albuquerque, M.P.

    1989-01-01

    The project and construction of four channel pulse generator in the S100 standard plate and its control software for microcomputer are described. The microcomputer has total control on the pulse generator, which has seven programable parameters, defining the position of four pulses and the width for the three first ones. This pulse generator is controlled by a software developed in c language, and is used in pulsed nuclear magnetic resonance experiences. (M.C.K.) [pt

  15. Characterisation by nuclear magnetic resonance of the β catalytic subunit of the chloroplastic coupling factor

    International Nuclear Information System (INIS)

    Andre, Francois

    1986-09-01

    This academic work addressed the use of nuclear magnetic resonance (NMR) for the structural and dynamic study of the catalytic sub-unit of the extrinsic section of a membrane complex, the chloroplastic H+-ATPase. This work included the development of a protocol of preparation and quantitative purification of β subunits isolated from the CF1 for the elaboration of a concentrated sample for NMR, and then the study of the β subunit by using proton NMR

  16. Development and applications of NMR [nuclear magnetic resonance] in low fields and zero field

    International Nuclear Information System (INIS)

    Bielecki, A.

    1987-05-01

    This dissertation is about nuclear magnetic resonance (NMR) spectroscopy in the absence of applied magnetic fields. NMR is usually done in large magnetic fields, often as large as can be practically attained. The motivation for going the opposite way, toward zero field, is that for certain types of materials, particularly powdered or polycrystalline solids, the NMR spectra in zero field are easier to interpret than those obtained in high field. 92 refs., 60 figs., 1 tab

  17. Hepatic Metabolism of Perfluorinated Carboxylic Acids and Polychlorotrifluoroethylene: A Nuclear Magnetic Resonance Investigation in Vivo

    Science.gov (United States)

    1994-01-05

    Goecke, L. Narayanan, and B. M. Jarnot. "Effects of Perfluoro-n- octanoic Acid , Perfluoro-n-decanoic Acid , and Clofibrate on Hepatic Phosphorus L...Carboxylic Acids and 4Polychiorotrifluoroethylene: A Nuclear Magnetic Resonance G-AFOSR-90-0148 Investigation in Vivo ,IIC 6. AUTHOR(S a Nicholas V. Reo...Maxim um 200 words) This report outlines our research progress regarding toxicological investigations of perifluoro- n-octanoic acid (PFOA) and

  18. Hepatic Metabolism of Perfluorinated Carboxylic Acids: A Nuclear Magnetic Resonance Investigation in Vivo

    Science.gov (United States)

    1995-01-17

    Reo, C. M. Goecke, L. Narayanan, and B. M. Jarnot. "Effects of Perfluoro-n- octanoic Acid , Perfluoro-n-decanoic Acid , and Clofibrate on Hepatic...SUBTITLE 7C 5. FUNDING NUMBERS" Hepatic Metabolism of Perfluorinated Carboxylic Acids : A Nuclear Magnetic Resonance Investigation in Vivo G-AFOSR-90-0148 6...octanoic acid (PFOA) and perfluoro-n-decanoic acid (PFDA). These Air Force chemicals belong to a class of CU’. compounds known as peroxisome

  19. Nuclear giant resonances in coordinate space. A semiclassical density functional approach

    International Nuclear Information System (INIS)

    Gleissl, P.; Brack, M.; Meyer, J.; Quentin, P.

    1987-01-01

    We discuss the semiclassical description of nuclear giant resonances (GR) using a realistic Skyrme force (SkM*) and complete ETF density functionals. We present monopole (0 + ) eigenmodes of isoscalar (I=0) and isovector (I=1) type, which are in good agreement with experiment, and the corresponding m 1 and m 3 sum rules. We also present the temperature dependence of some typical GR energies (0 + , I=0,1; 1 - , I=1; 2 + , I=0) in 208 Pb

  20. Advantages and disadvantages of nuclear magnetic resonance spectroscopy as a hyphenated technique

    International Nuclear Information System (INIS)

    Silva Elipe, Maria Victoria

    2003-01-01

    A general overview of the advancements and applications of nuclear magnetic resonance (NMR) hyphenated with other analytical techniques is given from a practical point of view. Details on the advantages and disadvantages of the hyphenation of NMR with liquid chromatography as LC-NMR and also with mass spectrometry as LC-MS-NMR are demonstrated with two examples. Current developments of NMR with other analytical separation techniques, especially with capillary liquid chromatography (capLC) are discussed

  1. Immediate analysis of the oil content of seeds by carbon-13 nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Leal, K Z; Costa, V E.U.; Seidl, P R; Campos, M P.A.; Colnago, L A [Instituto Militar de Engenharia, Rio de Janeiro (Brazil). Secao de Quimica

    1981-11-01

    The carbon 13 nuclear magnetic resonance (CMR) spectra of a series of Brazilian oilseeds was registered. The main constituents of the oils are identified and signals for each carbon atom are assigned. Chemical shifts are estimated for the free fatty acids and compared to those observed from the seeds, with good results. Besides being non-destructive, the RMC method proves to be fast and is useful in the determination of the principal components of the oil fraction of different types of seeds.

  2. Solid state nuclear magnetic resonance studies of prion peptides and proteins

    Energy Technology Data Exchange (ETDEWEB)

    Heller, Jonathan [Univ. of California, Berkeley, CA (United States)

    1997-08-01

    High-resolution structural studies using x-ray diffraction and solution nuclear magnetic resonance (NMR) are not feasible for proteins of low volubility and high tendency to aggregate. Solid state NMR (SSNMR) is in principle capable of providing structural information in such systems, however to do this efficiently and accurately, further SSNMR tools must be developed This dissertation describes the development of three new methods and their application to a biological system of interest, the priori protein (PrP).

  3. Display of cross sectional anatomy by nuclear magnetic resonance imaging. 1978.

    Science.gov (United States)

    Hinshaw, W S; Andrew, E R; Bottomley, P A; Holland, G N; Moore, W S

    1995-12-01

    High definition cross-sectional images produced by a new nuclear magnetic resonance (NMR) technique are shown. The images are a series of thin section scans in the coronal plane of the head of a rabbit. The NMR images are derived from the distribution of the density of mobile hydrogen atoms. Various tissue types can be distinguished and a clear registration of gross anatomy is demonstrated. No known hazards are associated with the technique.

  4. Nuclear magnetic resonance imaging of the knee: examples of normal anatomy and pathology.

    Science.gov (United States)

    Kean, D M; Worthington, B S; Preston, B J; Roebuck, E J; McKim-Thomas, H; Hawkes, R C; Holland, G N; Moore, W S

    1983-06-01

    Nuclear magnetic resonance images of the knee were obtained from three normal volunteers and from two patients. The pathology included an osteosarcoma of the distal femur and a fracture of the tibia. Steady State Free Precession (SSFP) techniques were used with a 0.15 Tesla resistive type magnet. Normal anatomy was well displayed and the size of the osteosarcoma was accurately predicted. Using SSFP techniques, the blood in the knee joint was not visualised, but the underlying tibial fracture was clearly outlined.

  5. Theory and applications of maps on SO(3) in nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Cho, H.M.

    1987-02-01

    Theoretical approaches and experimental work in the design of multiple pulse sequences in Nuclear Magnetic Resonance (NMR) are the subjects of this dissertation. Sequences of discrete pulses which reproduce the nominal effect of single pulses, but over substantially broader, narrower, or more selective ranges of transition frequencies, radiofrequency field amplitudes, and spin-spin couplings than the single pulses they replace, are developed and demonstrated. 107 refs., 86 figs., 6 tabs

  6. Pulsed-field gradient nuclear magnetic resonance study of transport properties of fluid catalytic cracking catalysts

    Czech Academy of Sciences Publication Activity Database

    Kortunov, P.; Vasenkov, S.; Kärger, J.; Fé Elía, M.; Perez, M.; Stöcker, M.; Papadopoulos, G. K.; Theodorou, D.; Drescher, B.; McElhiney, G.; Bernauer, B.; Krystl, V.; Kočiřík, Milan; Zikánová, Arlette; Jirglová, Hana; Berger, C.; Gläser, R.; Weitkamp, J.; Hansen, E. W.

    2005-01-01

    Roč. 23, č. 2 (2005), s. 233-237 ISSN 0730-725X Grant - others:TROCAT project - European Community(DE) G5RD-CT-2001-00520 Institutional research plan: CEZ:AV0Z40400503 Keywords : pulsed-field gradient * nuclear magnetic resonance * fluid catalytic cracking catalyst Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.361, year: 2005

  7. Two-dimensional J-resolved nuclear magnetic resonance spectral study of two bromobenzene glutathione conjugates

    Energy Technology Data Exchange (ETDEWEB)

    Ferretti, J.A.; Highet, R.J.; Pohl, L.R.; Monks, T.J.; Hinson, J.A.

    1985-09-01

    The application of two-dimensional J-resolved nuclear magnetic resonance spectroscopy to determine the structure of two bile metabolites isolated from rats injected interperitoneally with bromobenzene is described. The structures of the two molecules are obtained unambiguously from the proton-proton spin coupling constants. The paper discusses the fundamentals of the technique and demonstrates the resolution of small long-range coupling constants.

  8. 1H and 31P nuclear magnetic resonance spectroscopy of erythrocyte extracts in myotonic muscular dystrophy

    International Nuclear Information System (INIS)

    Gadoth, N.; Grinblat, J.; Tel Aviv Univ.; Shvo, H.; Navon, G.

    1984-01-01

    Extracts freshly prepared from erythrocytes of patients with myotonic muscular dystrophy, their unaffected siblings, and normal control subjects were examined with both 1 H and 31 P nuclear magnetic resonance spectroscopy. A moderate variability was found in the relative amounts of various nonphosphorylated compounds among patients and control subjects; however, no significant differences were found between the groups. As for the phosphorylated compounds, the sum of ADP+ATP was found significantly elevated in the myotonic muscular dystrophy patients

  9. Assessment of tumor energy and oxygenation status by bioluminescence, nuclear magnetic resonance spectroscopy, and cryospectrophotometry.

    Science.gov (United States)

    Mueller-Klieser, W; Schaefer, C; Walenta, S; Rofstad, E K; Fenton, B M; Sutherland, R M

    1990-03-15

    The energy and oxygenation status of tumors from two murine sarcoma lines (KHT, RIF-1) and two human ovarian carcinoma xenograft lines (MLS, OWI) were assessed using three independent techniques. Tumor energy metabolism was investigated in vivo by 31P nuclear magnetic resonance spectroscopy. After nuclear magnetic resonance measurements, tumors were frozen in liquid nitrogen to determine the tissue ATP concentration by imaging bioluminescence and to register the intracapillary oxyhemoglobin (HbO2) saturation using the cryospectrophotometric method. There was a positive correlation between the nucleoside triphosphate beta/total resonance ratio or a negative correlation between the Pi/total resonance ratio and the model ATP concentration obtained by bioluminescence, respectively. This was true for small tumors with no extended necrosis irrespective of tumor type. Moreover, a positive correlation was obtained between the HbO2 saturations and the ATP concentration measured with bioluminescence. The results demonstrate the potential of combined studies using noninvasive, integrating methods and high-resolution imaging techniques for characterizing the metabolic milieu in tumors.

  10. Resonance-inclined optical nuclear spin polarization of liquids in diamond structures

    Science.gov (United States)

    Chen, Q.; Schwarz, I.; Jelezko, F.; Retzker, A.; Plenio, M. B.

    2016-02-01

    Dynamic nuclear polarization (DNP) of molecules in a solution at room temperature has the potential to revolutionize nuclear magnetic resonance spectroscopy and imaging. The prevalent methods for achieving DNP in solutions are typically most effective in the regime of small interaction correlation times between the electron and nuclear spins, limiting the size of accessible molecules. To solve this limitation, we design a mechanism for DNP in the liquid phase that is applicable for large interaction correlation times. Importantly, while this mechanism makes use of a resonance condition similar to solid-state DNP, the polarization transfer is robust to a relatively large detuning from the resonance due to molecular motion. We combine this scheme with optically polarized nitrogen-vacancy (NV) center spins in nanodiamonds to design a setup that employs optical pumping and is therefore not limited by room temperature electron thermal polarization. We illustrate numerically the effectiveness of the model in a flow cell containing nanodiamonds immobilized in a hydrogel, polarizing flowing water molecules 4700-fold above thermal polarization in a magnetic field of 0.35 T, in volumes detectable by current NMR scanners.

  11. Resonance

    DEFF Research Database (Denmark)

    Petersen, Nils Holger

    2014-01-01

    A chapter in a book about terminology within the field of medievalism: the chapter discusses the resonance of medieval music and ritual in modern (classical) music culture and liturgical practice.......A chapter in a book about terminology within the field of medievalism: the chapter discusses the resonance of medieval music and ritual in modern (classical) music culture and liturgical practice....

  12. Properties of K,Rb-intercalated C60 encapsulated inside carbon nanotubes called peapods derived from nuclear magnetic resonance

    KAUST Repository

    Mahfouz, Remi; Bouhrara, M.; Kim, Y.; Wå gberg, T.; Goze-Bac, C.; Abou-Hamad, Edy

    2015-01-01

    We present a detailed experimental study on how magnetic and electronic properties of Rb,K-intercalated C60 encapsulated inside carbon nanotubes called peapods can be derived from 13C nuclear magnetic resonance investigations. Ring currents do play

  13. Revised rates for the stellar triple-α process from measurement of ¹²C nuclear resonances

    CERN Multimedia

    2005-01-01

    In the centres of stars where the temperature is high enough, three α-particles (helium nuclei) are able to combine to form ¹²C because of a resonant reaction leading to a nuclear excited state (2 pages)

  14. Advances in gamma ray resonant scattering and absorption long-lived isomeric nuclear states

    CERN Document Server

    Davydov, Andrey V

    2015-01-01

    This book presents the basics and advanced topics of research of gamma ray physics. It describes measuring of  Fermi surfaces with gamma resonance spectroscopy and the theory of angular distributions of resonantly scattered gamma rays. The dependence of excited-nuclei average lifetime on the shape of the exciting-radiation spectrum and electron binding energies in the spectra of scattered gamma rays is described. Resonant excitation by gamma rays of nuclear isomeric states with long lifetime leads to the emission and absorption lines. In the book, a new gamma spectroscopic method, gravitational gamma spectrometry, is developed. It has a resolution hundred million times higher than the usual Mössbauer spectrometer. Another important topic of this book is resonant scattering of annihilation quanta by nuclei with excited states in connection with positron annihilation. The application of the methods described is to explain the phenomenon of Coulomb fragmentation of gamma-source molecules and resonant scatt...

  15. Right and left ventricular performance by nuclear stethoscope

    International Nuclear Information System (INIS)

    Nishimura, T.; Uehara, T.; Hayashida, K.; Kozuka, T.

    1983-01-01

    Right and left ventricular performance by Nuclear Stethoscope using Kr-81m and Tc-99m-RBC were performed. And physiological and pharmacological interventions were also investigated for the evaluation of coronary artery diseases (CAD)

  16. Assessment of radiation injuries: role of nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Khushu, Subhash; Rana, Poonam

    2014-01-01

    In the event of an intentional or accidental release of ionizing radiation, timely assessment of the radiation exposure is critical for the triage and to facilitate timely and optimal medical care to the effected population. In addition to mild to severe injuries to tissues and organs, radiation injury can also cause cognitive decline, depressive behavior and affective state disturbances following exposure to both high and low doses of radiation. These may be even seen without evident tissue injury within hours to days or months to years after exposure to low doses of radiation. In this study, we exploited the multi-parametric contrast of NMR/MRI and its potential to assess radiation dose absorbed and radiation sickness thereof. High resolution NMR spectroscopy experiments were conducted on urine and serum samples collected from mice irradiated (whole body and focal irradiation) with 3, 5 and 8 Gray of γ-radiation at different time points post irradiation. Irradiated mice serum and urine showed distinct metabolic phenotypes and revealed dose and time dependent clustering of irradiated groups depicting different phases of radiation sickness. Increased concentration of urine metabolites related to gut microflora and energy metabolism were observed during different phases of radiation sickness. On the other hand serum spectra reflected changes associated with lipid, energy and membrane metabolism during radiation sickness. In vivo NMR spectroscopy and Diffusion Tensor Imaging (DTI) was also performed in different regions of brain post irradiation in animal model, which showed radiation induced metabolite changes in hippocampus region. Fractional anisotropy (FA) and mean diffusivity (MD) also demonstrated dose related changes in various brain regions which corroborated well with the behavioral parameters. The results of the present work lay a scientific foundation for development of high throughput radiation bio-dosimetry. This could further be useful in development

  17. Proton resonance spectroscopy. Final performance report, June 1987 - May 1996

    International Nuclear Information System (INIS)

    Shriner, J.F. Jr.

    1998-09-01

    This report gives a brief summary of accomplishments made on this project. Approximately 22 refereed papers were published with support from this grant; reprints are attached with this report. Topics studied include amplitude distributions in proton resonance reactions, chaos in nuclei, and tests of detailed balance and of parity violation with resonance reactions. Appendix 1 lists personnel and collaborators associated with this work, including the undergraduate students hired with grant funds, while Appendix 2 provides a list of talks, abstracts, dissertations and theses, etc. associated with the work supported by this grant

  18. Proton resonance spectroscopy. Final performance report, June 1987--May 1996

    Energy Technology Data Exchange (ETDEWEB)

    Shriner, J.F. Jr.

    1998-09-01

    This report gives a brief summary of accomplishments made on this project. Approximately 22 refereed papers were published with support from this grant; reprints are attached with this report. Topics studied include amplitude distributions in proton resonance reactions, chaos in nuclei, and tests of detailed balance and of parity violation with resonance reactions. Appendix 1 lists personnel and collaborators associated with this work, including the undergraduate students hired with grant funds, while Appendix 2 provides a list of talks, abstracts, dissertations and theses, etc. associated with the work supported by this grant.

  19. Time differentiated nuclear resonance spectroscopy coupled with pulsed laser heating in diamond anvil cells

    Energy Technology Data Exchange (ETDEWEB)

    Kupenko, I., E-mail: kupenko@esrf.fr; Strohm, C. [Bayerisches Geoinstitut, Universität Bayreuth, D-95440 Bayreuth (Germany); ESRF-The European Synchrotron, CS 40220, 38043 Grenoble Cedex 9 (France); McCammon, C.; Cerantola, V.; Petitgirard, S.; Dubrovinsky, L. [Bayerisches Geoinstitut, Universität Bayreuth, D-95440 Bayreuth (Germany); Glazyrin, K. [Photon Science, DESY, D-22607 Hamburg (Germany); Vasiukov, D.; Aprilis, G. [Laboratory of Crystallography, Material Physics and Technology at Extreme Conditions, Universität Bayreuth, D-95440 Bayreuth (Germany); Chumakov, A. I.; Rüffer, R. [ESRF-The European Synchrotron, CS 40220, 38043 Grenoble Cedex 9 (France)

    2015-11-15

    Developments in pulsed laser heating applied to nuclear resonance techniques are presented together with their applications to studies of geophysically relevant materials. Continuous laser heating in diamond anvil cells is a widely used method to generate extreme temperatures at static high pressure conditions in order to study the structure and properties of materials found in deep planetary interiors. The pulsed laser heating technique has advantages over continuous heating, including prevention of the spreading of heated sample and/or the pressure medium and, thus, a better stability of the heating process. Time differentiated data acquisition coupled with pulsed laser heating in diamond anvil cells was successfully tested at the Nuclear Resonance beamline (ID18) of the European Synchrotron Radiation Facility. We show examples applying the method to investigation of an assemblage containing ε-Fe, FeO, and Fe{sub 3}C using synchrotron Mössbauer source spectroscopy, FeCO{sub 3} using nuclear inelastic scattering, and Fe{sub 2}O{sub 3} using nuclear forward scattering. These examples demonstrate the applicability of pulsed laser heating in diamond anvil cells to spectroscopic techniques with long data acquisition times, because it enables stable pulsed heating with data collection at specific time intervals that are synchronized with laser pulses.

  20. Nuclear magnetic resonance-based metabolomics for prediction of gastric damage induced by indomethacin in rats

    International Nuclear Information System (INIS)

    Um, So Young; Park, Jung Hyun; Chung, Myeon Woo; Kim, Kyu-Bong; Kim, Seon Hwa; Choi, Ki Hwan; Lee, Hwa Jeong

    2012-01-01

    Highlights: ► NMR based metabolomics – gastric damage by indomethacin. ► Pattern recognition analysis was performed to biomarkers of gastric damage. ► 2-Oxoglutarate, acetate, taurine and hippurate were selected as putative biomarkers. ► The gastric damage induced by NSAIDs can be screened in the preclinical step of drug. - Abstract: Non-steroidal anti-inflammatory drugs (NSAIDs) have side effects including gastric erosions, ulceration and bleeding. In this study, pattern recognition analysis of the 1 H-nuclear magnetic resonance (NMR) spectra of urine was performed to develop surrogate biomarkers related to the gastrointestinal (GI) damage induced by indomethacin in rats. Urine was collected for 5 h after oral administration of indomethacin (25 mg kg −1 ) or co-administration with cimetidine (100 mg kg −1 ), which protects against GI damage. The 1 H-NMR urine spectra were divided into spectral bins (0.04 ppm) for global profiling, and 36 endogenous metabolites were assigned for targeted profiling. The level of gastric damage in each animal was also determined. Indomethacin caused severe gastric damage; however, indomethacin administered with cimetidine did not. Simultaneously, the patterns of changes in their endogenous metabolites were different. Multivariate data analyses were carried out to recognize the spectral pattern of endogenous metabolites related to indomethacin using partial least square-discrimination analysis. In targeted profiling, a few endogenous metabolites, 2-oxoglutarate, acetate, taurine and hippurate, were selected as putative biomarkers for the gastric damage induced by indomethacin. These metabolites changed depending on the degree of GI damage, although the same dose of indomethacin (10 mg kg −1 ) was administered to rats. The results of global and targeted profiling suggest that the gastric damage induced by NSAIDs can be screened in the preclinical stage of drug development using a NMR based metabolomics approach.

  1. Nuclear magnetic resonance-based metabolomics for prediction of gastric damage induced by indomethacin in rats

    Energy Technology Data Exchange (ETDEWEB)

    Um, So Young [Department of Pharmacology, National Institute of Toxicological Research, Korea Food and Drug Administration, 643 Yeonje-ri, Gangoe-myeon, Cheongwon-gun, Chungbuk (Korea, Republic of); Division of Life and Pharmaceutical Science and College of Pharmacy, Ewha Womans University, 52 Ewahyeodae-gil, Seodaemun-gu, Seoul (Korea, Republic of); Park, Jung Hyun [Division of Life and Pharmaceutical Science and College of Pharmacy, Ewha Womans University, 52 Ewahyeodae-gil, Seodaemun-gu, Seoul (Korea, Republic of); Chung, Myeon Woo [Department of Pharmacology, National Institute of Toxicological Research, Korea Food and Drug Administration, 643 Yeonje-ri, Gangoe-myeon, Cheongwon-gun, Chungbuk (Korea, Republic of); Kim, Kyu-Bong [College of Pharmacy, Dankook University, Dandae-ro, Cheonan, Chungnam (Korea, Republic of); Kim, Seon Hwa [Department of Pharmacology, National Institute of Toxicological Research, Korea Food and Drug Administration, 643 Yeonje-ri, Gangoe-myeon, Cheongwon-gun, Chungbuk (Korea, Republic of); Division of Life and Pharmaceutical Science and College of Pharmacy, Ewha Womans University, 52 Ewahyeodae-gil, Seodaemun-gu, Seoul (Korea, Republic of); College of Pharmacy, Dankook University, Dandae-ro, Cheonan, Chungnam (Korea, Republic of); Choi, Ki Hwan, E-mail: hyokwa11@korea.kr [Department of Pharmacology, National Institute of Toxicological Research, Korea Food and Drug Administration, 643 Yeonje-ri, Gangoe-myeon, Cheongwon-gun, Chungbuk (Korea, Republic of); Lee, Hwa Jeong, E-mail: hwalee@ewha.ac.kr [Division of Life and Pharmaceutical Science and College of Pharmacy, Ewha Womans University, 52 Ewahyeodae-gil, Seodaemun-gu, Seoul (Korea, Republic of)

    2012-04-13

    Highlights: Black-Right-Pointing-Pointer NMR based metabolomics - gastric damage by indomethacin. Black-Right-Pointing-Pointer Pattern recognition analysis was performed to biomarkers of gastric damage. Black-Right-Pointing-Pointer 2-Oxoglutarate, acetate, taurine and hippurate were selected as putative biomarkers. Black-Right-Pointing-Pointer The gastric damage induced by NSAIDs can be screened in the preclinical step of drug. - Abstract: Non-steroidal anti-inflammatory drugs (NSAIDs) have side effects including gastric erosions, ulceration and bleeding. In this study, pattern recognition analysis of the {sup 1}H-nuclear magnetic resonance (NMR) spectra of urine was performed to develop surrogate biomarkers related to the gastrointestinal (GI) damage induced by indomethacin in rats. Urine was collected for 5 h after oral administration of indomethacin (25 mg kg{sup -1}) or co-administration with cimetidine (100 mg kg{sup -1}), which protects against GI damage. The {sup 1}H-NMR urine spectra were divided into spectral bins (0.04 ppm) for global profiling, and 36 endogenous metabolites were assigned for targeted profiling. The level of gastric damage in each animal was also determined. Indomethacin caused severe gastric damage; however, indomethacin administered with cimetidine did not. Simultaneously, the patterns of changes in their endogenous metabolites were different. Multivariate data analyses were carried out to recognize the spectral pattern of endogenous metabolites related to indomethacin using partial least square-discrimination analysis. In targeted profiling, a few endogenous metabolites, 2-oxoglutarate, acetate, taurine and hippurate, were selected as putative biomarkers for the gastric damage induced by indomethacin. These metabolites changed depending on the degree of GI damage, although the same dose of indomethacin (10 mg kg{sup -1}) was administered to rats. The results of global and targeted profiling suggest that the gastric damage induced by

  2. Effects of CO2 injection and Kerogen Maturation on Low-Field Nuclear Magnetic Resonance Response

    Science.gov (United States)

    Prasad, M.; Livo, K.

    2017-12-01

    Low-field Nuclear Magnetic Resonance (NMR) is commonly used in petrophysical analysis of petroleum reservoir rocks. NMR experiments record the relaxation and polarization of in-situ hydrogen protons present in gaseous phases such as free-gas intervals and solution gas fluids, bulk fluid phases such as oil and aquifer intervals, and immovable fractions of kerogen and bitumen. Analysis of NMR relaxation spectra is performed to record how fluid composition, maturity, and viscosity change NMR experimental results. We present T1-T2 maps as thermal maturity of a water-saturated, sub-mature Woodford shale is increased at temperatures from 125 to 400 degrees Celsius. Experiments with applied fluid pressure in paraffinic mineral oil and DI water with varying fluid pH have been performed to mimic reservoir conditions in analysis of the relaxation of bulk fluid phases. We have recorded NMR spectra, T1-T2 maps, and fluid diffusion coefficients using a low-field (2 MHz) MagritekTM NMR. CO2 was injected at a pressure of 900 psi in an in house developed NMR pressure vessel made of torlon plastic. Observable 2D NMR shifts in immature kerogen formations as thermal maturity is increased show generation of lighter oils with increased maturity. CO2 injection leads to a decrease in bulk fluid relaxation time that is attributed to viscosity modification with gas presence. pH variation with increased CO2 presence were shown to not effect NMR spectra. From this, fluid properties have been shown to greatly affect NMR readings and must be taken into account for more accurate NMR reservoir characterization.

  3. A nuclear magnetic resonance and electron spin resonance study on the dynamics of pentacoordinated organophosphorus compounds

    International Nuclear Information System (INIS)

    Keijzer, A.E.H. de.

    1988-01-01

    In this thesis the role of the steric and electronic effects on the fundamental dynamic behaviour of pentacoordinated phosporus compounds is further elaborated. In chapter 2 a variable temperature 13 C NMR study, performed on a series of monocyclic oxyphosphoranes, is presented. The investigations were carried out to determine the influence of the conformational transmission effect on the barriers to pseudorotation in pentacoordinated phosphorus compounds. Chapter 3 also comprises a variable temperature 13 C NMR study on pentacoordinated phosphorus compounds. In this chapter, however, an additional high-resolution 1 H NMR study on the conformational equilibria around the P-O-C-C-O fragments is included. These studies were performed in order to determine whether the enhancement of the reorganization rates around phosphorus is brought about by accelerated pseudorotation or by the involvement of hexacoordinated zwitterionic phosphorus intermediates. In chapter 4, a 31 P NMR study on the solvolysis rate of several phosphinate esters is described. This study was performed in order to determine the influence of the conformational transmission effect on the solvolysis rate of phosphate esters. A number of phosphates is examined in which, during the course of the solvolysis reaction, the conformational transmission effect is bound to be present or absent respectively. Moreover, it is discussed in which way the concept of conformational transmission induced differences in solvolysis rates can be used as a probe to examine the reactions of biologically important phosphate esters. In chapters 5 and 6 ESR studies on the influence of steric and electronic factors on phosphoranyl formation in solution, and on the intramolecular electron transfer in phosphoranyl radicals are presented. (author). 121 refs.; 33 figs.; 17 figs

  4. Nuclear structure studies of rare francium isotopes using Collinear Resonance Ionization Spectroscopy (CRIS)

    CERN Document Server

    AUTHOR|(CDS)2084441

    It was known for many years that nuclei possessing certain numbers of protons (Z) and neutrons (N), called the magic numbers (8,20,28,50,82,126...), exhibit characteristic behavior and are in general more stable than their neighboring isotopes. As the capabilities of producing isotopes with more extreme values of Z and N increased, it was realized that those spherical nuclei only represent a small fraction of the total number of isotopes and that most isotopes are deformed. In order to study exotic isotopes and their deformation, it was necessary to develop new experimental techniques that would be powerful enough to be able to cope with very small production yields, but precise enough to measure the nuclear properties (such as radii and moments) with relatively small uncertainties. One technique that can measure nuclear properties of scarcely produced isotopes is in-source resonant ionization, but this technique does not allow for sufficient precision to deduce nuclear quadrupole moments. Furthermore, this t...

  5. Fluorine nuclear magnetic resonance study of enrichment effects in gaseous, liquid and solid uranium hexafluoride

    International Nuclear Information System (INIS)

    Ursu, I.; Demco, D.E.; Simplaceanu, V.; Valcu, N.

    1977-01-01

    The nuclear magnetic resonance method is able to provide information concerning the isotopic content of 235 U in UF 6 by means of measuring the nuclear magnetic transverse relaxation time (T,L2) of 19 F nuclei in liquid UF 6 . In this work, the sources of errors in the T 2 measurements have been analysed and methods for reducing them are dicussed. Typical errors in T 2 determinations are below 2%. The enrichment estimations made by using the linear calibration curves had a deviation of less than 2% with some exceptions. It was found that the chemical impurities may significantly affect the enrichment estimations. 19 F NMR spectra of liquid and gaseous UF 6 at low pressures did not reveal any structure or enrichment effect. The longitudinal nuclear magnetic relaxation of 19 F nuclei in low pressure, gaseous and solid UF 6 showed no enrichment dependence, nor the dipolar relaxation time in solid UF 6 did. (author)

  6. Nuclear spin cooling by electric dipole spin resonance and coherent population trapping

    Science.gov (United States)

    Li, Ai-Xian; Duan, Su-Qing; Zhang, Wei

    2017-09-01

    Nuclear spin fluctuation suppression is a key issue in preserving electron coherence for quantum information/computation. We propose an efficient way of nuclear spin cooling in semiconductor quantum dots (QDs) by the coherent population trapping (CPT) and the electric dipole spin resonance (EDSR) induced by optical fields and ac electric fields. The EDSR can enhance the spin flip-flop rate and may bring out bistability under certain conditions. By tuning the optical fields, we can avoid the EDSR induced bistability and obtain highly polarized nuclear spin state, which results in long electron coherence time. With the help of CPT and EDSR, an enhancement of 1500 times of the electron coherence time can been obtained after a 500 ns preparation time.

  7. Nuclear magnetic resonance with dc SQUID [Super-conducting QUantum Interference Device] preamplifiers

    International Nuclear Information System (INIS)

    Fan, N.Q.; Heaney, M.B.; Clark, J.; Newitt, D.; Wald, L.; Hahn, E.L.; Bierlecki, A.; Pines, A.

    1988-08-01

    Sensitive radio-frequency (rf) amplifiers based on dc Superconducting QUantum Interface Devices (SQUIDS) are available for frequencies up to 200 MHz. At 4.2 K, the gain and noise temperature of a typical tuned amplifier are 18.6 +- 0.5 dB and 1.7 +- 0.5 K at 93 MHz. These amplifiers are being applied to a series of novel experiments on nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR). The high sensitivity of these amplifiers was demonstrated in the observation of ''nuclear spin noise'', the emission of photons by 35 Cl nuclei in a state of zero polarization. In the more conventional experiments in which one applies a large rf pulse to the spins, a Q-spoiler, consisting of a series array of Josephson junctions, is used to reduce the Q of the input circuit to a very low value during the pulse. The Q-spoiler enables the circuit to recover quickly after the pulse, and has been used in an NQR experiment to achieve a sensitivity of about 2 /times/ 10 16 nuclear Bohr magnetons in a single free precession signal with a bandwidth of 10 kHz. In a third experiment, a sample containing 35 Cl nuclei was placed in a capacitor and the signal detected electrically using a tuned SQUID amplifier and Q-spoiler. In this way, the electrical polarization induced by the precessing Cl nuclear quadrupole moments was detected: this is the inverse of the Stark effect in NQR. Two experiments involving NMR have been carried out. In the first, the 30 MHz resonance in 119 Sn nuclei is detected with a tuned amplifier and Q-spoiler, and a single pulse resolution of 10 18 nuclear Bohr magnetons in a bandwidth of 25 kHz has been achieved. For the second, a low frequency NMR system has been developed that uses an untuned input circuit coupled to the SQUID. The resonance in 195 Pt nuclei has been observed at 55 kHz in a field of 60 gauss. 23 refs., 11 figs

  8. Performances of nuclear installations in the world

    International Nuclear Information System (INIS)

    Pate, Z.T.

    1999-01-01

    During the last years the operators of nuclear power plants in the world, have realized numerous improvements. This success is imputable to several factors, especially an important data exchange. The Chernobyl accident, in 1986, provoked the creation of the World Association of Nuclear Operators (W.A.N.O.). It allowed to exchange information and to develop cooperation in order to go beyond cultural barriers, linguistics and policies. Then, operators in the world have brought important improvements in matter of safety, reliability. (N.C.)

  9. Performance of monolayer graphene nanomechanical resonators with electrical readout.

    Science.gov (United States)

    Chen, Changyao; Rosenblatt, Sami; Bolotin, Kirill I; Kalb, William; Kim, Philip; Kymissis, Ioannis; Stormer, Horst L; Heinz, Tony F; Hone, James

    2009-12-01

    The enormous stiffness and low density of graphene make it an ideal material for nanoelectromechanical applications. Here, we demonstrate the fabrication and electrical readout of monolayer graphene resonators, and test their response to changes in mass and temperature. The devices show resonances in the megahertz range, and the strong dependence of resonant frequency on applied gate voltage can be fitted to a membrane model to yield the mass density and built-in strain of the graphene. Following the removal and addition of mass, changes in both density and strain are observed, indicating that adsorbates impart tension to the graphene. On cooling, the frequency increases, and the shift rate can be used to measure the unusual negative thermal expansion coefficient of graphene. The quality factor increases with decreasing temperature, reaching approximately 1 x 10(4) at 5 K. By establishing many of the basic attributes of monolayer graphene resonators, the groundwork for applications of these devices, including high-sensitivity mass detectors, is put in place.

  10. Observation of Motion of Bowed Strings and Resonant Strings in Violin Performances

    Science.gov (United States)

    Matsutani, Akihiro

    2013-10-01

    The motion of a bowed string and a resonant string of a violin were simultaneously observed for the first time. The results of the direct observation of string motion in double stops and harmonics are also presented. The importance of the resonance was experimentally demonstrated from these observations. It is suggested that players should take account of the resonance and ideal Helmholtz motion in violin performances.

  11. Utility of magnetic resonance imaging and nuclear magnetic resonance-based metabolomics for quantification of inflammatory lung injury

    Science.gov (United States)

    Serkova, Natalie J.; Van Rheen, Zachary; Tobias, Meghan; Pitzer, Joshua E.; Wilkinson, J. Erby; Stringer, Kathleen A.

    2008-01-01

    Magnetic resonance imaging (MRI) and metabolic nuclear magnetic resonance (NMR) spectroscopy are clinically available but have had little application in the quantification of experimental lung injury. There is a growing and unfulfilled need for predictive animal models that can improve our understanding of disease pathogenesis and therapeutic intervention. Integration of MRI and NMR could extend the application of experimental data into the clinical setting. This study investigated the ability of MRI and metabolic NMR to detect and quantify inflammation-mediated lung injury. Pulmonary inflammation was induced in male B6C3F1 mice by intratracheal administration of IL-1β and TNF-α under isoflurane anesthesia. Mice underwent MRI at 2, 4, 6, and 24 h after dosing. At 6 and 24 h lungs were harvested for metabolic NMR analysis. Data acquired from IL-1β+TNF-α-treated animals were compared with saline-treated control mice. The hyperintense-to-total lung volume (HTLV) ratio derived from MRI was higher in IL-1β+TNF-α-treated mice compared with control at 2, 4, and 6 h but returned to control levels by 24 h. The ability of MRI to detect pulmonary inflammation was confirmed by the association between HTLV ratio and histological and pathological end points. Principal component analysis of NMR-detectable metabolites also showed a temporal pattern for which energy metabolism-based biomarkers were identified. These data demonstrate that both MRI and metabolic NMR have utility in the detection and quantification of inflammation-mediated lung injury. Integration of these clinically available techniques into experimental models of lung injury could improve the translation of basic science knowledge and information to the clinic. PMID:18441091

  12. Nuclear resonance scattering of synchrotron radiation as a unique electronic, structural and thermodynamic probe

    International Nuclear Information System (INIS)

    Alp, E. Ercan; Sturhahn, Wolfgang; Toellner, Thomas S.; Zhao, Jiyong; Leu, Bogdan M.

    2012-01-01

    Discovery of Moessbauer effect in a nuclear transition was a remarkable development. It revealed how long-lived nuclear states with relatively low energies in the kiloelectron volt (keV) region can be excited without recoil. This new effect had a unique feature involving a coupling between nuclear physics and solid-state physics, both in terms of physics and sociology. Physics coupling originates from the fact that recoilless emission and absorption or resonance is only possible if the requirement that nuclei have to be bound in a lattice with quantized vibrational states is fulfilled, and that the finite electron density on the nucleus couples to nuclear degrees of freedom leading to hyperfine interactions. thus, Moessbauer spectroscopy allows peering into solid-state effects using unique nuclear transitions. Sociological aspects of this coupling had been equally startling and fruitful. The interaction between diverse scientific communities, who learned to use Moessbauer spectroscopy proved to be very valuable. For example, biologists, geologists, chemists, physics, materials scientists, and archeologists, all sharing a common spectroscopic technique, also learned to appreciate the beauty and intricacies of each other's fields. As a laboratory-based technique, Moessbauer spectroscopy matured by the end of the 1970s. Further exciting developments took place when accelerator-based techniques were employed, like synchrotron radiation or 'in-beam'Moessbauer experiments with implanted radioactive ions. More recently, two Moessbauer spectrometers on the surface of the Mars kept the technique vibrant and viable up until present time. In this chapter, the authors look into some of the unique aspects of nuclear resonance excited with synchrotron radiation as a probe of condensed matter, including magnetism, valence, vibrations, and lattice dynamics, and review the development of nuclear resonance inelastic x-ray scattering (NRIXS) and synchrotron Moessbauer spectroscopy

  13. Experience with performance based training of nuclear criticality safety engineers

    International Nuclear Information System (INIS)

    Taylor, R.G.

    1993-01-01

    For non-reactor nuclear facilities, the U.S. Department of Energy (DOE) does not require that nuclear criticality safety engineers demonstrate qualification for their job. It is likely, however, that more formalism will be required in the future. Current DOE requirements for those positions which do have to demonstrate qualification indicate that qualification should be achieved by using a systematic approach such as performance based training (PBT). Assuming that PBT would be an acceptable mechanism for nuclear criticality safety engineer training in a more formal environment, a site-specific analysis of the nuclear criticality safety engineer job was performed. Based on this analysis, classes are being developed and delivered to a target audience of newer nuclear criticality safety engineers. Because current interest is in developing training for selected aspects of the nuclear criticality safety engineer job, the analysis is incompletely developed in some areas

  14. Calculation of the probability of overlapping one family of nuclear levels with resonances of an independent family

    International Nuclear Information System (INIS)

    Difilippo, F.C.

    1982-01-01

    Calculations of the resonance integrals of particular isotopes in a mixture of isotopes show that the overlapping of the resonances of one isotope by resonances of other isotopes affects the final values of effective cross sections. The same effect might adversely influence those nondestructive techniques which assay fissile materials on the basis of resonance effects. Of relevance for these applications is the knowledge of the probability of overlapping resonances of a family of nuclear levels (class 1) with resonances of an independent family (class 2). For the sequence of class 1 resonances we calculate the probability distribution, p(delta), to find a class 2, first-neighbor resonance at distance (in energy) delta from a class 1 resonance; integration of p(delta) over the average finite width of the resonances would give the aforementioned probability of overlapping. Because a class 1 resonance can have a class 1 or a class 2 resonance as a first neighbor, the resultant p(delta) is not given by the distribution of spacings of the composite family

  15. Three dimensional nuclear magnetic resonance spectroscopic imaging of sodium ions using stochastic excitation and oscillating gradients

    International Nuclear Information System (INIS)

    Frederick, B.deB.

    1994-12-01

    Nuclear magnetic resonance (NMR) spectroscopic imaging of 23 Na holds promise as a non-invasive method of mapping Na + distributions, and for differentiating pools of Na + ions in biological tissues. However, due to NMR relaxation properties of 23 Na in vivo, a large fraction of Na + is not visible with conventional NMR imaging methods. An alternate imaging method, based on stochastic excitation and oscillating gradients, has been developed which is well adapted to measuring nuclei with short T 2 . Contemporary NMR imaging techniques have dead times of up to several hundred microseconds between excitation and sampling, comparable to the shortest in vivo 23 Na T 2 values, causing significant signal loss. An imaging strategy based on stochastic excitation has been developed which greatly reduces experiment dead time by reducing peak radiofrequency (RF) excitation power and using a novel RF circuit to speed probe recovery. Continuously oscillating gradients are used to eliminate transient eddy currents. Stochastic 1 H and 23 Na spectroscopic imaging experiments have been performed on a small animal system with dead times as low as 25μs, permitting spectroscopic imaging with 100% visibility in vivo. As an additional benefit, the encoding time for a 32x32x32 spectroscopic image is under 30 seconds. The development and analysis of stochastic NMR imaging has been hampered by limitations of the existing phase demodulation reconstruction technique. Three dimensional imaging was impractical due to reconstruction time, and design and analysis of proposed experiments was limited by the mathematical intractability of the reconstruction method. A new reconstruction method for stochastic NMR based on Fourier interpolation has been formulated combining the advantage of a several hundredfold reduction in reconstruction time with a straightforward mathematical form

  16. Absolute quantitative analysis for sorbic acid in processed foods using proton nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Ohtsuki, Takashi; Sato, Kyoko; Sugimoto, Naoki; Akiyama, Hiroshi; Kawamura, Yoko

    2012-01-01

    Highlights: ► A method using qHNMR was applied and validated to determine SA in processed foods. ► This method has good accuracy, precision, selectiveness, and linearity. ► The proposed method is more rapid and simple than the conventional method. ► We found that the proposed method is reliable for the accurate determination of SA. ► This method can be used for the monitoring of SA in processed foods. - Abstract: An analytical method using solvent extraction and quantitative proton nuclear magnetic resonance (qHNMR) spectroscopy was applied and validated for the absolute quantification of sorbic acid (SA) in processed foods. The proposed method showed good linearity. The recoveries for samples spiked at the maximum usage level specified for food in Japan and at 0.13 g kg −1 (beverage: 0.013 g kg −1 ) were larger than 80%, whereas those for samples spiked at 0.063 g kg −1 (beverage: 0.0063 g kg −1 ) were between 56.9 and 83.5%. The limit of quantification was 0.063 g kg −1 for foods (and 0.0063 g kg −1 for beverages containing Lactobacillus species). Analysis of the SA content of commercial processed foods revealed quantities equal to or greater than those measured using conventional steam-distillation extraction and high-performance liquid chromatography quantification. The proposed method was rapid, simple, accurate, and precise, and provided International System of Units traceability without the need for authentic analyte standards. It could therefore be used as an alternative to the quantification of SA in processed foods using conventional method.

  17. Absolute quantitative analysis for sorbic acid in processed foods using proton nuclear magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ohtsuki, Takashi, E-mail: ohtsuki@nihs.go.jp [National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501 (Japan); Sato, Kyoko; Sugimoto, Naoki; Akiyama, Hiroshi; Kawamura, Yoko [National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501 (Japan)

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer A method using qHNMR was applied and validated to determine SA in processed foods. Black-Right-Pointing-Pointer This method has good accuracy, precision, selectiveness, and linearity. Black-Right-Pointing-Pointer The proposed method is more rapid and simple than the conventional method. Black-Right-Pointing-Pointer We found that the proposed method is reliable for the accurate determination of SA. Black-Right-Pointing-Pointer This method can be used for the monitoring of SA in processed foods. - Abstract: An analytical method using solvent extraction and quantitative proton nuclear magnetic resonance (qHNMR) spectroscopy was applied and validated for the absolute quantification of sorbic acid (SA) in processed foods. The proposed method showed good linearity. The recoveries for samples spiked at the maximum usage level specified for food in Japan and at 0.13 g kg{sup -1} (beverage: 0.013 g kg{sup -1}) were larger than 80%, whereas those for samples spiked at 0.063 g kg{sup -1} (beverage: 0.0063 g kg{sup -1}) were between 56.9 and 83.5%. The limit of quantification was 0.063 g kg{sup -1} for foods (and 0.0063 g kg{sup -1} for beverages containing Lactobacillus species). Analysis of the SA content of commercial processed foods revealed quantities equal to or greater than those measured using conventional steam-distillation extraction and high-performance liquid chromatography quantification. The proposed method was rapid, simple, accurate, and precise, and provided International System of Units traceability without the need for authentic analyte standards. It could therefore be used as an alternative to the quantification of SA in processed foods using conventional method.

  18. Quantitative determination of Quarternary alicyclic carbon atoms in coal and oil using nuclear magnetic resonance /sup 13/C method

    Energy Technology Data Exchange (ETDEWEB)

    Afonina, T.V.; Kushnarev, D.F.; Randin, O.I.; Shishkov, V.F.; Kalabin, G.A.

    1986-09-01

    Possibility is indicated for utilizing nuclear magnetic resonance spectroscopy for quantitative determination of Quarternary aliphatic carbon atoms in heavy hydrocarbon fractions of oil and coal extracts. C/sub n/, CH, CH/sub 2/ and CH/sub 3/ content in coal and oil samples are determined and corresponding resonance lines are referred to individual structural fragments (on the basis of nuclear magnetic resonance /sup 13/C spectra) of known saturated hydrocarbons. Tests were carried out on chloroform extracts of Irsha-Borodinsk coal, Mungunsk coal and paraffin and cycloparaffin of Sivinsk oil (b.p. over 550 C) fractions. Nuclear magnetic resonance spectra were obtained using Burker WP 200 spectrometer (50.13 MHz frequency). Results of the tests are given. 11 references.

  19. Using international experience to improve performance of nuclear power plants

    International Nuclear Information System (INIS)

    Calori, F.; Csik, B.J.; Strickert, R.J.

    1989-01-01

    Information on performance achievements will assist nuclear power plant operating organizations to develop initiatives for improved or continued high performance of their plants. The paper describes the activities of the IAEA in reviewing and analysing the reasons for good performance by contacting operating organizations identified by its Power Reactor Information System as showing continued good performance. Discussions with operations personnel of utilities have indicated practices which have a major positive impact on good performance and which are generally common to all well performing organizations contacted. The IAEA also promotes further activities directed primarily to the achievement of standards of excellence in nuclear power operation. These are briefly commented

  20. High-pressure nuclear magnetic resonance studies of fuel cell membranes

    Science.gov (United States)

    Mananga, Eugene Stephane

    water at different concentrations: proton (1H) and phosphorus (31P) nuclei have been performed using the static field gradient spin-echo nuclear magnetic resonance. This study is expected to be helpful in improving the understanding of phosphoric acid fuel cell technology.

  1. /sup 14/N nuclear quadrupole resonance in ferroelectric sodium nitrite NaNO/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S; Singh, K [Defence Science Lab., Delhi (India)

    1974-06-01

    Nuclear quadrupole resonance has been studied in ferroelectric sodium nitrite (NaNO/sub 2/) from 77 K to its phase transition point 437 K. The three rotational frequencies ..omega../sub c/ = 190 cm/sup -1/, ..omega../sub b/ = 120 cm/sup -1/ and ..omega../sub c/ = 227 cm/sup -1/ and their temperature variation when fitted in the Bayer-Kushida theory predict the temperature dependence of nqr frequencies reasonably well. A second order phase transition is found to occur at 180 K which is in confirmity with the one found earlier from thermal expansion and dielectric studies. The shift in resonance frequencies is seen to occur mainly by rotation around the 'c' axis and hence it is inferred that the mechanism of polarization reversal is intimately connected with orientational motion about 'c' axis. (auth)

  2. Analysis of ringing effects due to magnetic core materials in pulsed nuclear magnetic resonance circuits

    International Nuclear Information System (INIS)

    Prabhu Gaunkar, N.; Bouda, N. R. Y.; Nlebedim, I. C.; Hadimani, R. L.; Mina, M.; Jiles, D. C.; Bulu, I.; Ganesan, K.; Song, Y. Q.

    2015-01-01

    This work presents investigations and detailed analysis of ringing in a non-resonant pulsed nuclear magnetic resonance (NMR) circuit. Ringing is a commonly observed phenomenon in high power switching circuits. The oscillations described as ringing impede measurements in pulsed NMR systems. It is therefore desirable that those oscillations decay fast. It is often assumed that one of the causes behind ringing is the role of the magnetic core used in the antenna (acting as an inductive load). We will demonstrate that an LRC subcircuit is also set-up due to the inductive load and needs to be considered due to its parasitic effects. It is observed that the parasitics associated with the inductive load become important at certain frequencies. The output response can be related to the response of an under-damped circuit and to the magnetic core material. This research work demonstrates and discusses ways of controlling ringing by considering interrelationships between different contributing factors

  3. Use of nuclear magnetic resonance of hydrogen in the characterization of saturated hydrocarbonic chains

    International Nuclear Information System (INIS)

    Costa Neto, A.; Soares, V.L.P.; Costa Neto, C.

    1979-01-01

    Alkanes and cycloalkanes are characterized by a methyl-methylene-methine groups proportion, the percentual absorption in prefixed regions and the pattern of the spectrum of nuclear magnetic resonance of hydrogen. The GPI is calculated from the contribution of the areas corresponding to prefixed regions of the hydrogen magnetic resonance spectra (60 Mc). These regions are (for the saturated hydrocarbons): 0,5-1,05ppm (X), 1,05ppm (Y) and 1,50-2,00ppm (Z). The validity of the index was verified for the homologous series of linear hydrocarbons and methyl-, dimethyl-, ethyl-, cyclopentyl- and cyclohexyl-branched hydrocarbons. Its application to shale oil chemistry (xistoquimica) is discussed. (author) [pt

  4. Nuclear magnetic resonance studies of intracellular ions in perfused from heart

    International Nuclear Information System (INIS)

    Burnstein, D.; Fossel, E.T.

    1987-01-01

    Intracellular sodium, potassium, and lithium were observed in a perfused frog heart by nuclear magnetic resonance (NMR) spectroscopy. A perfusate buffer containing the shift reagent, dysprosium tripolyphosphate, was used in combination with mathematical filtering or presaturation of the extracellular resonance to separate the intra- and extracellular sodium NMR signals. Addition of 10 μM ouabain to the perfusate, perfusion with a zero potassium, low-calcium buffer, and replacement of 66% of the perfusate sodium with lithium resulted in changes in the intracellular sodium levels. An increase of 45% in the intracellular sodium was observed when changing the pacing rate from 0 to 60 beats/min (with proportional changes for intermediate pacing rates). The ratio of intracellular potassium to sodium concentration was determined to be 2.3 by NMR, indicating that a substantial amount of the intracellular potassium is undetectable with these NMR method. In addition, intracellular lithium was observed during perfusion with a lithium-containing perfusate

  5. Motor circuit computer model based on studies of functional Nuclear Magnetic Resonance

    International Nuclear Information System (INIS)

    Garcia Ramo, Karla Batista; Rodriguez Rojas, Rafael; Carballo Barreda, Maylen

    2012-01-01

    The basal ganglia are a complex network of subcortical nuclei involved in motor control, sensorimotor integration, and cognitive processes. Their functioning and interaction with other cerebral structures remains as a subject of debate. The aim of the present work was to simulate the basal ganglia-thalamus-cortex circuitry interaction in motor program selection, supported by functional connectivity pattern obtained by functional nuclear magnetic resonance imaging. Determination of connections weights between neural populations by functional magnetic resonance imaging, contributed to a more realistic formulation of the model; and consequently to obtain similar results to clinical and experimental data. The network allowed to describe the participation of the basal ganglia in motor program selection and the changes in Parkinson disease. The simulation allowed to demonstrate that dopamine depletion above to 40 % leads to a loss of action selection capability, and to reflect the system adaptation ability to compensate dysfunction in Parkinson disease, coincident with experimental and clinical studies

  6. Analysis of ringing effects due to magnetic core materials in pulsed nuclear magnetic resonance circuits

    Energy Technology Data Exchange (ETDEWEB)

    Prabhu Gaunkar, N., E-mail: neelampg@iastate.edu; Bouda, N. R. Y.; Nlebedim, I. C.; Hadimani, R. L.; Mina, M.; Jiles, D. C. [Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011 (United States); Bulu, I.; Ganesan, K.; Song, Y. Q. [Schlumberger-Doll Research, Cambridge, Massachusetts 02139 (United States)

    2015-05-07

    This work presents investigations and detailed analysis of ringing in a non-resonant pulsed nuclear magnetic resonance (NMR) circuit. Ringing is a commonly observed phenomenon in high power switching circuits. The oscillations described as ringing impede measurements in pulsed NMR systems. It is therefore desirable that those oscillations decay fast. It is often assumed that one of the causes behind ringing is the role of the magnetic core used in the antenna (acting as an inductive load). We will demonstrate that an LRC subcircuit is also set-up due to the inductive load and needs to be considered due to its parasitic effects. It is observed that the parasitics associated with the inductive load become important at certain frequencies. The output response can be related to the response of an under-damped circuit and to the magnetic core material. This research work demonstrates and discusses ways of controlling ringing by considering interrelationships between different contributing factors.

  7. Performance of PWR Nuclear power plants, up to 1985

    International Nuclear Information System (INIS)

    Muniz, A.A.

    1987-01-01

    The performance of PWR nuclear power plants is studied, based on operational data up to 1985. The availability analysis was made with 793 unit-year and the reliability analysis was made with 5851 unit x month. The results were discussed and the availability of those nuclear power plants were estimated. (E.G.) [pt

  8. Contribution to the study of nuclear resonance in magnetic media (1963); Contribution a l'etude de la resonance nucleaire dans les milieux magnetique (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann-Boutron, F [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-06-15

    An attempt is made to interpret the results of nuclear magnetic resonance experiments made by various workers on ferro and ferrimagnetic compounds of the iron group. The problems encountered are the following: effects of the dipolar fields and the hyperfine structure anisotropy; signal intensity; frequency pulling due to the Suhl-Nakamura interaction between nuclear spins ; nuclear relaxation and ferrimagnetic resonance in single domain samples of impure YIG; nuclear relaxation in the Bloch walls of insulators. The results of our calculations are generally in good agreement with experiment. (author) [French] On se propose d'interpreter les resultats d'experiences de resonance magnetique nucleaire fates par divers auteurs sur des composes ferro et ferrimagnetiques du groupe du fer. Les problemes abordes sont les suivants: effets des champs dipolaires et de l'anisotropie de structure hyperfine; intensite des signaux; deplacement de frequence du a l'interaction de Suhl-Nakamura entre spins nucleaires; relaxation nucleaire et resonance ferrimagnetique dans les echantillons monodomaines de grenat de fer et d'yttrium impur; relaxation nucleaire dans les parois de Bloch des isolants. Les resultats des calculs sont generalement en bon accord avec l'experience. (auteur)

  9. Contribution to the study of nuclear resonance in magnetic media (1963); Contribution a l'etude de la resonance nucleaire dans les milieux magnetique (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann-Boutron, F. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-06-15

    An attempt is made to interpret the results of nuclear magnetic resonance experiments made by various workers on ferro and ferrimagnetic compounds of the iron group. The problems encountered are the following: effects of the dipolar fields and the hyperfine structure anisotropy; signal intensity; frequency pulling due to the Suhl-Nakamura interaction between nuclear spins ; nuclear relaxation and ferrimagnetic resonance in single domain samples of impure YIG; nuclear relaxation in the Bloch walls of insulators. The results of our calculations are generally in good agreement with experiment. (author) [French] On se propose d'interpreter les resultats d'experiences de resonance magnetique nucleaire fates par divers auteurs sur des composes ferro et ferrimagnetiques du groupe du fer. Les problemes abordes sont les suivants: effets des champs dipolaires et de l'anisotropie de structure hyperfine; intensite des signaux; deplacement de frequence du a l'interaction de Suhl-Nakamura entre spins nucleaires; relaxation nucleaire et resonance ferrimagnetique dans les echantillons monodomaines de grenat de fer et d'yttrium impur; relaxation nucleaire dans les parois de Bloch des isolants. Les resultats des calculs sont generalement en bon accord avec l'experience. (auteur)

  10. Nuclear fuel performance in boiling water reactors

    International Nuclear Information System (INIS)

    Elkins, R.B.; Baily, W.E.; Proebstle, R.A.; Armijo, J.S.; Klepfer, H.H.

    1981-01-01

    A major development program is described to improve the performance of Boiling Water Reactor fuel. This sustained program is described in four parts: 1) performance monitoring, 2) fuel design changes, 3) plant operating recommendations, and 4) advanced fuel programs

  11. The performance of nuclear power plants

    International Nuclear Information System (INIS)

    1989-07-01

    A survey is presented of failures in the Dutch nuclear power plants Borssele (10) and Dodewaard (5) reported during the year 1988. This reporting takes place, since 1987, on the basis of the international failure-reporting system. This system is based on the 'Incident Reporting System' of the IAEA. During 1988 no failures did occur which made particular safety measurements necessary. Also these failures did not have any consequence for the environment. During all failures the reactor safety system of both power plants did operate well. (H.W.)

  12. Immediate analysis of the oil content of seeds by carbon-13 nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Leal, K.Z.; Costa, V.E.U.; Seidl, P.R.; Campos, M.P.A.; Colnago, L.A.

    1981-01-01

    The carbon 13 nuclear magnetic resonance (CMR) spectra of a series of Brazilian oilseeds was registered. The main constituents of the oils are identified and signals for each carbon atom are assigned. Chemical shifts are estimated for the free fatty acids and compared to those observed from the seeds, with good results. Besides being non-destructive, the RMC method proves to be fast and is useful in the determination of the principal components of the oil fraction of different types of seeds. (Author) [pt

  13. Nuclear magnetic resonance and sound velocity measurements of chalk saturated with magnesium rich brine

    DEFF Research Database (Denmark)

    Katika, Konstantina; Alam, Mohammad Monzurul; Fabricius, Ida Lykke

    2013-01-01

    The use of low field Nuclear Magnetic Resonance (NMR) to determine petrophysical properties of reservoirs has proved to be a good technique. Together with sonic and electrical resistivity measurements, NMR can contribute to illustrate the changes on chalk elasticity due to different pore water...... solutions of the same ionic strength. Saturation with a solution that contained divalent ions caused a major shift on the distribution of the relaxation time. The changes were probably due to precipitats forming extra internal surface in the sample. Sonic velocities were relatively low in the MgCl2 solution...

  14. Study and realisation of a programmable generator of pulse sequences, for nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Lambert, Daniel

    1974-01-01

    After having recalled the operation of pulse-based nuclear magnetic resonance and the use of pulse sequences in NMR-based measurements, and outlined the need for a pulse sequence generator, the author reports the design and realisation of such a device. He describes its general organisation with its base sequence, base clock, sequence start, duration, displays, data transfers, data processing, and signal distribution. He presents the chosen technology (ECL logics), the sequence base set, time bases, multiplexers, comparison sets, the distribution set, the sequence programming, the sampling and output set. He reports tests and the use of the so-designed generator [fr

  15. Cranial anatomy and detection of ischemic stroke in the cat by nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Buonanno, F.S.; Pykett, I.L.; Kistler, J.P.; Vielma, J.; Brady, T.J.; Hinshaw, W.S.; Goldman, M.R.; Newhouse, J.H.; Pohost, G.M.

    1982-01-01

    Proton nuclear magnetic resonance (NMR) images of cat heads were obtained using a small, experimental imaging system. As a prelude to the study of experimental ischemic brain infarction, the normal cat head was imaged for identification of anatomical features. Images of one cat which had undergone ligation of the middle cerebral artery three weeks previously showed brain changes associated with chronic ischemic stroke and compared favorably with findings on computed tomography (CT). The NMR images have millimetric spatial resolution. NMR parameters inherent in the tissues provide intensity variations and are sufficiently sensitive to yield contrast resolution surpassing that of CT

  16. The role of nuclear magnetic resonance imaging in the diagnosis of intracranial vascular malformation

    International Nuclear Information System (INIS)

    Ford, C.S.; Buonanno, F.S.; Kistler, J.P.; Johnson, K.A.

    1987-01-01

    Intracranial vascular malformations (ICVMs) usually present with seizures or intracranial hemorrhage. Less commonly, they cause headaches and transient or progressive focal neurologic deficits. Consecutive autopsy data show, however, that asymptomatic ICVMs are actually many times more common than symptomatic ones. Asymptomatic ICVMs are often never detected. Recognition of ICVMs is further hindered by the fact that cerebral angiography and computed tomography are normal in many cases. A review is given of the cerebral angiograms, and the CT and nuclear magnetic resonance (NMR) scans in a group of patients with ICVM to study the role of NMR in making the diagnosis. 5 refs.; 1 figure

  17. Molecular Structure Laboratory. Fourier Transform Nuclear Magnetic Resonance (FTNMR) Spectrometer and Ancillary Instrumentation at SUNY Geneseo

    Energy Technology Data Exchange (ETDEWEB)

    Geiger, David K [State Univ. of New York (SUNY), Geneseo, NY (United States)

    2015-12-31

    An Agilent 400-MR nuclear magnetic resonance (NMR) spectrometer and ancillary equipment were purchased, which are being used for molecular structure elucidation.  The instrumentation is housed in a pre-existing facility designed specifically for its use. This instrument package is being used to expand the research and educational efforts of the faculty and students at SUNY-Geneseo and is made available to neighboring educational institutions and business concerns.  Funds were also used for training of College personnel, maintenance of the instrumentation, and installation of the equipment.

  18. Electromagnetic properties of inner double walled carbon nanotubes investigated by nuclear magnetic resonance

    KAUST Repository

    Bouhrara, M.; Abou-Hamad, E.; Alabedi, G.; Al-Taie, I.; Kim, Y.; Wagberg, T.; Goze-Bac, C.

    2013-01-01

    The nuclear magnetic resonance (NMR) analytical technique was used to investigate the double walled carbon nanotubes (DWNTs) electromagnetic properties of inner walls. The local magnetic and electronic properties of inner nanotubes in DWNTs were analyzed using 25% 13C enriched C 60 by which the effect of dipolar coupling could be minimized. The diamagnetic shielding was determined due to the ring currents on outer nanotubes in DWNTs. The NMR chemical shift anisotropy (CSA) spectra and spin-lattice relaxation studies reveal the metallic properties of the inner nanotubes with a signature of the spin-gap opening below 70 K.

  19. Increase of the assistancial productivity of the nuclear magnetic resonance equipment TOMIKON BMT 1100

    International Nuclear Information System (INIS)

    Rodriguez, A.; Carbonell, G.; Hernandez, C.

    1992-01-01

    In the present work a revision of the physical parameters which take part in the obtained of the Nuclear Magnetic Resonance (NMR) is carried put. Image is obtained introducing changes on them given in the disminution of the matrix size from 256 x 256 to 128 pixels with the corresponding disminution of FOV in dependence of the analized region, showing theoretical and practically its great importance of the number of possible examination with the resulting augment of the productivity of the method and the possibility to carried out studies on little cooperative patients mantaining an adequate quality and diagnostic information of the images

  20. An interferometric complementarity experiment in a bulk nuclear magnetic resonance ensemble

    International Nuclear Information System (INIS)

    Peng Xinhua; Zhu Xiwen; Fang Ximing; Feng Mang; Liu Maili; Gao Kelin

    2003-01-01

    We have experimentally demonstrated the interferometric complementarity, which relates the distinguishability D quantifying the amount of which-way (WW) information to the fringe visibility V characterizing the wave feature of a quantum entity, in a bulk ensemble by nuclear magnetic resonance (NMR) techniques. We are primarily concerned about the intermediate cases: partial fringe visibility and incomplete WW information. We propose a quantitative measure of D by an alternative geometric strategy and investigate the relation between D and entanglement. By measuring D and V independently, it turns out that the duality relation D 2 + V 2 = 1 holds for pure quantum states of the markers

  1. Ferromagnetic nuclear resonance investigation of the surface magnetization in iron sheets

    International Nuclear Information System (INIS)

    Varga, L.; Tompa, K.

    1977-09-01

    The role of the domain structure and domain properties in ferromagnetic nuclear resonance (FNR) experiments is reconsidered. Using the FNR signal intensity as a measure of surface domain wall volume, it is found that the behaviour of the surface magnetization differs from that of the bulk magnetization of iron sheets. Namely, a critical field below which the FNR signal remains unchanqed is observed in the surface magnetization. This lag of surface domain wall annihilation is sensitive to the given surface conditions and in particular to the rolling deformation. Considering the small skin depth, FNR as a surface testing method is discussed. (D.P.)

  2. Development of Nuclear Magnetic Resonance Imaging/spectroscopy for improved petroleum recovery. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Barrufet, M.A.; Flumerfelt, F.W.; Walsh, M.P.; Watson, A.T.

    1994-04-01

    The overall objectives of this program are to develop and apply Nuclear Magnetic Resonance Imaging (NMRI) and CT X-Ray Scanning methods for determining rock, fluid, and petrophysical properties and for fundamental studies of multiphase flow behavior in porous media. Specific objectives are divided into four subtasks: (1) development of NMRI and CT scanning for the determination of rock-fluid and petrophysical properties; (2) development of NMRI and CT scanning for characterizing conventional multiphase displacement processes; (3) development of NMR and CT scanning for characterizing dispersed phase processes; and (4) miscible displacement studies.

  3. Measure of hydrogen concentration profile in materials by resonant nuclear reactions

    International Nuclear Information System (INIS)

    Livi, R.P.; Zawislak, F.C.; Acquadro, J.C.

    1986-01-01

    The technique for determining the profile of hydrogen concentration in proximities of the surface of materials, is presented. The preliminary measurements were done, using the Pelletron accelerator at Sao Paulo University (USP), in Brazil, for the resonant-nuclear reaction 1 H( 19 F, α γ) 16 O. By using this reaction the technique is sensitive for concentrations above 500 ppm, which could be reduced to 100 ppm through special shieldings and other techniques to reduce the background radiation. (M.C.K.) [pt

  4. Realization of quantum state privacy amplification in a nuclear magnetic resonance quantum system

    International Nuclear Information System (INIS)

    Hao, Liang; Wang, Chuan; Long, Gui Lu

    2010-01-01

    Quantum state privacy amplification (QSPA) is the quantum analogue of classical privacy amplification. If the state information of a series of single-particle states has some leakage, QSPA reduces this leakage by condensing the state information of two particles into the state of one particle. Recursive applications of the operations will eliminate the quantum state information leakage to a required minimum level. In this paper, we report the experimental implementation of a quantum state privacy amplification protocol in a nuclear magnetic resonance system. The density matrices of the states are constructed in the experiment, and the experimental results agree well with theory.

  5. Nuclear magnetic resonance zeugmatographic imaging of the heart: application to the study of ventricular septal defect

    International Nuclear Information System (INIS)

    Heneghan, M.A.; Biancaniello, T.M.; Heidel, E.; Peterson, S.B.; Marsh, M.J.; Lauterbur, P.C.

    1982-01-01

    The present work was undertaken to determine the applicability of nuclear magnetic resonance (NMR) imaging to the study of congenital heart disease. Three-dimensional proton density images of preserved lamb hearts with and without an artificially created ventricular septal defect were reconstructed and displayed in multiple planes. Sections obtained in the sagittal plane through the ventricular septum clearly showed the size, shape, and location of the defect. Results of these experiments suggest that NMR zeugmatography will become a valuable addition to existing imaging techniques for the study of congenital heart disease

  6. Recent Advances in Computational Methods for Nuclear Magnetic Resonance Data Processing

    KAUST Repository

    Gao, Xin

    2013-01-11

    Although three-dimensional protein structure determination using nuclear magnetic resonance (NMR) spectroscopy is a computationally costly and tedious process that would benefit from advanced computational techniques, it has not garnered much research attention from specialists in bioinformatics and computational biology. In this paper, we review recent advances in computational methods for NMR protein structure determination. We summarize the advantages of and bottlenecks in the existing methods and outline some open problems in the field. We also discuss current trends in NMR technology development and suggest directions for research on future computational methods for NMR.

  7. Resonances

    DEFF Research Database (Denmark)

    an impetus or drive to that account: change, innovation, rupture, or discontinuity. Resonances: Historical Essays on Continuity and Change explores the historiographical question of the modes of interrelation between these motifs in historical narratives. The essays in the collection attempt to realize...

  8. Preliminary Study of the Efficacy of Using Nuclear Resonance Fluorescence with Quasi-Monoenergetic Gamma-Ray Sources for Nuclear Safeguards Assay

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, M S; McNabb, D P; Hall, J M; Gonzalez, J J

    2011-02-17

    We have studied the efficacy of using nuclear resonance fluorescence (NRF)-based techniques to assay spent nuclear fuel for Pu content using quasi-monoenergetic sources. We have developed two techniques to precisely determine the Pu content in a fuel rod/pin. One of our approaches is virtually free of systematic uncertainties. Using analytical models, we have determined the amount of time required to measure the Pu content in spent nuclear fuel rods and spent fuel assemblies to within 1% precision. We note that Pu content can be determined in a fuel assembly about as fast as in a single fuel pin. The performance of NRF-based assay techniques with improved photon sources, which are currently under development, will also estimated. For follow-on research we propose to: (1) Construct research prototype detection systems for both of the NRF-based assay systems proposed in this paper and measure their calibration curves; (2) Determine the systematic errors associated with both assay methods, explore ways to reduce the errors and fold the results into future performance calculations; (3) Develop an algorithm to assay a fuel assembly; (4) Perform validation measurements using a single pin and scaled assemblies; (5) Research and develop current-mode detection and/or threshold detection techniques to improve assay times; (6) Characterize the flux of newly constructed sources and fold the results into the calculations presented here to determine the feasibility of a variety of proposed sources; and (7) Collaborate with others in the safeguards community to build a prototype system and perform an NRF-based assay demonstration on spent fuel.

  9. Human performance improvement for nuclear power plants

    International Nuclear Information System (INIS)

    2005-01-01

    The IAEA assists NPP operating organizations to improve plant performance through a focus on human performance improvement in areas like organizational and leadership development, senior management decision making, organization and management of HPI programmes including tools needed for effective HPI implementation, safety culture enhancement, knowledge management, personnel selection and staffing, career development, training and development, work design, scheduling and conditions, procedure and other job-aid development and use, effective communications, human performance monitoring, motivation. Many NPP operating organizations in Member States, are not yet achieving the full potential of their NPP technology/equipment regarding safety, operational or economic performance due to human performance weaknesses. The IAEA's HPI (Human Performance Improvement) services provide a means for these organizations to efficiently and effectively learn from international experts and the experiences of others in improving plant performance through human performance improvements. NPP operating organizations can benefit from these services in a number of ways, including requesting a national project, participating in a regional project, or requesting an assist visit. The types of activities provided through these services include assistance in benchmarking practices of successful organizations, providing information exchange and reviews of current practices through assist missions, conducting workshops on focused human performance topics, evaluating current human performance methods, including assistance in implementing self assessment programmes and providing support to safety culture enhancement programmes based on self-assessment

  10. A magnet without a magnetic circuit, of high homogeneity, specially for nuclear magnetic resonance images

    International Nuclear Information System (INIS)

    Barjhoux, Yves.

    1981-01-01

    This invention concerns a high homogeneity, double access magnet without a magnetic circuit. It is specially adapted for nuclear magnetic resonance (N.M.R.) imagery. Another advantage worth stressing resides in the possibilities of NMR in biochemical analysis which will enable, for instance, cancerous tumours to be detected in vivo. In order to increase the NMR signal ratio over background noise, it is necessary to increase the homogeneity of the B 0 orientating magnetic field. This magnetic field must orientate the nuclear magnetic moments of the elementary particles which compose the body being examined and in particular the protons. It must therefore be relatively constant in intensity and direction in the entire domain of the examination [fr

  11. Substitution effect in nuclear magnetic resonance of C-13: α methoxicyclohexanones

    International Nuclear Information System (INIS)

    Lopez Holland, M.A.G.

    1984-01-01

    Eletronic and steric interactions between the carbonyl and methoxyl groups in α-methoxicyclohexanones by H-1 and C-13 nuclear magnetic resonance spectroscopy (n.m.r) is studied. Interpretation of H-1 n.m.r measurements based on the carbonyl group anisotropy is made. The asigment of spectral lines to specific nuclear by Lanthanide Shift Reagent Experiments is confirmed. Interpretation of C-13 n.m.r. spectra with respect to molecular effects and emphirical relationships associated with the substituent was analysed. The C-13 chemical shift asignment by comparison with results of partially (SFORD) and fully decompled spectra and also by relating the measured chemical shift with values cited in the literature for similar compounds are made. A qualitative study using I.R. spectroscopy in attempt to evaluate the predominance of one the conformers of the studied compounds in solutions of n-hexan and chloroform is made. (M.J.C.) [pt

  12. 13C nuclear magnetic resonance study of the complexation of calcium by taurine

    International Nuclear Information System (INIS)

    Irving, C.S.; Hammer, B.E.; Danyluk, S.S.; Klein, P.D.

    1980-01-01

    13 C Nuclear magnetic resonance chemical shifts, 1 J/sub c-c/ scalar coupling constants, spin-lattice relaxation times, and nuclear Overhauser effects were determined for taurine-[1, 2 13 C] and a taurine-[1 13 C] and taurine-[2 13 C] mixture in the presence and absence of calcium. Comparison of taurine titration shifts to values for related compounds reveals some unusual electronic properties of the taurine molecule. Stability constants of 1:1 calcium complexes with taurine zwitterions and anions, as well as their 13 C chemical shifts, were obtained by least squares analysis of titration curves measured in the presence of calcium. The stability constants of calcium-taurine complexes were significantly lower than previous values and led to estimates that only approximately one percent of intracellular calcium of mammalian myocardial cells would exist in a taurine complex

  13. Relativistic effects in the intermolecular interaction-induced nuclear magnetic resonance parameters of xenon dimer

    DEFF Research Database (Denmark)

    Hanni, Matti; Lantto, Perttu; Ilias, Miroslav

    2007-01-01

    Relativistic effects on the 129Xe nuclear magnetic resonance shielding and 131Xe nuclear quadrupole coupling (NQC) tensors are examined in the weakly bound Xe2 system at different levels of theory including the relativistic four-component Dirac-Hartree-Fock (DHF) method. The intermolecular...... interaction-induced binary chemical shift d, the anisotropy of the shielding tensor ?s, and the NQC constant along the internuclear axis ?ll are calculated as a function of the internuclear distance. DHF shielding calculations are carried out using gauge-including atomic orbitals. For comparison, the full...... is obtained for d and ?s in Xe2. For these properties, the currently most complete theoretical description is obtained by a piecewise approximation where the uncorrelated relativistic DHF results obtained close to the basis-set limit are corrected, on the one hand, for NR correlation effects and, on the other...

  14. Electron paramagnetic resonance and dynamic nuclear polarization of char suspensions: surface science and oximetry

    International Nuclear Information System (INIS)

    Clarkson, R.B.; Odintsov, B.M.; Ceroke, P.J.; Ardenkjaer-Larsen, J.H.; Fruianu, M.; Belford, R.L.

    1998-01-01

    Carbon chars have been synthesized in our laboratory from a variety of starting materials, by means of a highly controlled pyrolysis technique. These chars exhibit electron paramagnetic resonance (EPR) line shapes which change with the local oxygen concentration in a reproducible and stable fashion; they can be calibrated and used for oximetry. Biological stability and low toxicity make chars good sensors for in vivo measurements. Scalar and dipolar interactions of water protons at the surfaces of chars may be utilized to produce dynamic nuclear polarization (DNP) of the 1 H nuclear spin population in conjunction with electron Zeeman pumping. Low-frequency EPR, DNP and DNP-enhanced MRI all show promise as oximetry methods when used with carbon chars. (author)

  15. Nuclear resonance scattering study of iridates, iridium and antimony based pyrochlores

    International Nuclear Information System (INIS)

    Alexeev, P.

    2017-04-01

    This thesis shows the first synchrotron-based Moessbauer spectroscopy studies on iridium containing compounds and first vibrational spectroscopy on Sb containing compounds carried out at the P01 beamline of PETRA III. In this context, two types of X-ray monochromators have been developed: a monochromator for 73 keV photons with medium energy resolution, and a high-resolution backscattering monochromator based on a sapphire crystal. The monochromator for 73 keV X-rays is the key instrument for hyperfine spectroscopy on Iridium compounds, while the sapphire backscattering monochromator is purposed to vibrational spectroscopy on any Moessbauer resonances with the transition energies in the 20-50 keV range. Additionally, the signal detection for nuclear resonance scattering experiments at the beamline was significantly improved during this work, inspired by the high energies and low lifetimes of the employed resonances. The first synchrotron-based hyperfine spectroscopy on Iridium-containing compounds was demonstrated by NRS on 73 keV resonance in "1"9"3Ir. The results can be interpreted by dynamical theory of nuclear resonance scattering. In this work, special emphasis is set onto the electronic and magnetic properties of Ir nuclei in IrO_2 and in Ruddlesden-Popper (RP) phases of strontium iridates Sr_n_+_1Ir_nO_3_n_+_1 (n=0,1). These systems are well-suited for studies with X-ray scattering techniques, since the scattered signal contains vast information about the widely tunable crystallographic and electronic structure of these systems; furthermore, studies with X-rays are less limited by absorption from iridium as it is the case for neutron scattering experiments. The hyperfine parameters in IrO_2, SrIrO_3 and Sr_2IrO_4 have been measured via Nuclear Forward Scattering for the first time. Using the dynamical theory of NRS, the temperature and magnetic field dependence of the electric field gradient and magnetic hyperfine field on Ir nucleus have been determined for

  16. Nuclear resonance scattering study of iridates, iridium and antimony based pyrochlores

    Energy Technology Data Exchange (ETDEWEB)

    Alexeev, P.

    2017-04-15

    This thesis shows the first synchrotron-based Moessbauer spectroscopy studies on iridium containing compounds and first vibrational spectroscopy on Sb containing compounds carried out at the P01 beamline of PETRA III. In this context, two types of X-ray monochromators have been developed: a monochromator for 73 keV photons with medium energy resolution, and a high-resolution backscattering monochromator based on a sapphire crystal. The monochromator for 73 keV X-rays is the key instrument for hyperfine spectroscopy on Iridium compounds, while the sapphire backscattering monochromator is purposed to vibrational spectroscopy on any Moessbauer resonances with the transition energies in the 20-50 keV range. Additionally, the signal detection for nuclear resonance scattering experiments at the beamline was significantly improved during this work, inspired by the high energies and low lifetimes of the employed resonances. The first synchrotron-based hyperfine spectroscopy on Iridium-containing compounds was demonstrated by NRS on 73 keV resonance in {sup 193}Ir. The results can be interpreted by dynamical theory of nuclear resonance scattering. In this work, special emphasis is set onto the electronic and magnetic properties of Ir nuclei in IrO{sub 2} and in Ruddlesden-Popper (RP) phases of strontium iridates Sr{sub n+1}Ir{sub n}O{sub 3n+1} (n=0,1). These systems are well-suited for studies with X-ray scattering techniques, since the scattered signal contains vast information about the widely tunable crystallographic and electronic structure of these systems; furthermore, studies with X-rays are less limited by absorption from iridium as it is the case for neutron scattering experiments. The hyperfine parameters in IrO{sub 2}, SrIrO{sub 3} and Sr{sub 2}IrO{sub 4} have been measured via Nuclear Forward Scattering for the first time. Using the dynamical theory of NRS, the temperature and magnetic field dependence of the electric field gradient and magnetic hyperfine field

  17. Performance management for nuclear power plant operators

    International Nuclear Information System (INIS)

    Fan Pengfei

    2014-01-01

    Fuel was loaded to Unit 3 of the second power plant in May 2010. The Second Operation Division stepped in the operation stage from production preparation and commissioning and exploration of performance management was started. By means of performance evaluation, a closed loop of performance management was formed, staff enthusiasm improved, and potential capability inspired through evaluation, analysis and improvement. The performance evaluation covers attitude, skill, efficiency, performance, teamwork sense, cooperation, etc. Quantitative appraisal was carried out through 31 objective indicators of the working process and results. According to the evaluation results and personal interviews, indicators were modified. Through the performance evaluation, positive guidance is provided to the employees to promote the development of employees, departments and the enterprise. (authors)

  18. Nuclear magnetic resonance studies of quadrupolar nuclei and dipolar field effects

    International Nuclear Information System (INIS)

    Urban, Jeffry Todd

    2004-01-01

    Experimental and theoretical research conducted in two areas in the field of nuclear magnetic resonance (NMR) spectroscopy is presented: (1) studies of the coherent quantum-mechanical control of the angular momentum dynamics of quadrupolar (spin I > 1/2) nuclei and its application to the determination of molecular structure; and (2) applications of the long-range nuclear dipolar field to novel NMR detection methodologies.The dissertation is organized into six chapters. The first two chapters and associated appendices are intended to be pedagogical and include an introduction to the quantum mechanical theory of pulsed NMR spectroscopy and the time dependent theory of quantum mechanics. The third chapter describes investigations of the solid-state multiple-quantum magic angle spinning (MQMAS) NMR experiment applied to I 5/2 quadrupolar nuclei. This work reports the use of rotary resonance-matched radiofrequency irradiation for sensitivity enhancement of the I = 5/2 MQMAS experiment. These experiments exhibited certain selective line narrowing effects which were investigated theoretically.The fourth chapter extends the discussion of multiple quantum spectroscopy of quadrupolar nuclei to a mostly theoretical study of the feasibility of enhancing the resolution of nitrogen-14 NMR of large biomolecules in solution via double-quantum spectroscopy. The fifth chapter continues to extend the principles of multiple quantum NMR spectroscopy of quadrupolar nuclei to make analogies between experiments in NMR/nuclear quadrupolar resonance (NQR) and experiments in atomic/molecular optics (AMO). These analogies are made through the Hamiltonian and density operator formalism of angular momentum dynamics in the presence of electric and magnetic fields.The sixth chapter investigates the use of the macroscopic nuclear dipolar field to encode the NMR spectrum of an analyte nucleus indirectly in the magnetization of a sensor nucleus. This technique could potentially serve as an encoding

  19. Nuclear magnetic resonance studies of quadrupolar nuclei and dipolar field effects

    Energy Technology Data Exchange (ETDEWEB)

    Urban, Jeffry Todd [Univ. of California, Berkeley, CA (United States)

    2004-01-01

    Experimental and theoretical research conducted in two areas in the field of nuclear magnetic resonance (NMR) spectroscopy is presented: (1) studies of the coherent quantum-mechanical control of the angular momentum dynamics of quadrupolar (spin I > 1/2) nuclei and its application to the determination of molecular structure; and (2) applications of the long-range nuclear dipolar field to novel NMR detection methodologies.The dissertation is organized into six chapters. The first two chapters and associated appendices are intended to be pedagogical and include an introduction to the quantum mechanical theory of pulsed NMR spectroscopy and the time dependent theory of quantum mechanics. The third chapter describes investigations of the solid-state multiple-quantum magic angle spinning (MQMAS) NMR experiment applied to I = 5/2 quadrupolar nuclei. This work reports the use of rotary resonance-matched radiofrequency irradiation for sensitivity enhancement of the I = 5/2 MQMAS experiment. These experiments exhibited certain selective line narrowing effects which were investigated theoretically.The fourth chapter extends the discussion of multiple quantum spectroscopy of quadrupolar nuclei to a mostly theoretical study of the feasibility of enhancing the resolution of nitrogen-14 NMR of large biomolecules in solution via double-quantum spectroscopy. The fifth chapter continues to extend the principles of multiple quantum NMR spectroscopy of quadrupolar nuclei to make analogies between experiments in NMR/nuclear quadrupolar resonance (NQR) and experiments in atomic/molecular optics (AMO). These analogies are made through the Hamiltonian and density operator formalism of angular momentum dynamics in the presence of electric and magnetic fields.The sixth chapter investigates the use of the macroscopic nuclear dipolar field to encode the NMR spectrum of an analyte nucleus indirectly in the magnetization of a sensor nucleus. This technique could potentially serve as an

  20. Nuclear resonant scattering measurements on (57)Fe by multichannel scaling with a 64-pixel silicon avalanche photodiode linear-array detector.

    Science.gov (United States)

    Kishimoto, S; Mitsui, T; Haruki, R; Yoda, Y; Taniguchi, T; Shimazaki, S; Ikeno, M; Saito, M; Tanaka, M

    2014-11-01

    We developed a silicon avalanche photodiode (Si-APD) linear-array detector for use in nuclear resonant scattering experiments using synchrotron X-rays. The Si-APD linear array consists of 64 pixels (pixel size: 100 × 200 μm(2)) with a pixel pitch of 150 μm and depletion depth of 10 μm. An ultrafast frontend circuit allows the X-ray detector to obtain a high output rate of >10(7) cps per pixel. High-performance integrated circuits achieve multichannel scaling over 1024 continuous time bins with a 1 ns resolution for each pixel without dead time. The multichannel scaling method enabled us to record a time spectrum of the 14.4 keV nuclear radiation at each pixel with a time resolution of 1.4 ns (FWHM). This method was successfully applied to nuclear forward scattering and nuclear small-angle scattering on (57)Fe.

  1. The performance trends of nuclear power plants worldwide

    Energy Technology Data Exchange (ETDEWEB)

    Glorian, D. [Electricite de France (EDF), 93 - Saint-Denis (France)

    2001-07-01

    Looking back to the worldwide operating experience feedback, which performance trends and conclusions could be drawn up? What is the specific situation of the French nuclear units, in comparison with the average worldwide performance? The performance of a unit or group of facilities is measured not only in technical terms (safety, availability, load control capability), but also from an economic and financial standpoint (operating and maintenance costs, fuel costs, etc). Performance in terms of radiological protection and on-the-job safety, as well as environmental protection, is also monitored in order to give the broadest possible overview of nuclear power plant performance. The main technical results are presented on the basis of selected performance indicators. The results obtained by French units are benchmarked against those of other PWR facilities in operation around the world, in accordance with comparisons made by the World Association of Nuclear Operators (WANO). (author)

  2. The performance trends of nuclear power plants worldwide

    International Nuclear Information System (INIS)

    Glorian, D.

    2001-01-01

    Looking back to the worldwide operating experience feedback, which performance trends and conclusions could be drawn up? What is the specific situation of the French nuclear units, in comparison with the average worldwide performance? The performance of a unit or group of facilities is measured not only in technical terms (safety, availability, load control capability), but also from an economic and financial standpoint (operating and maintenance costs, fuel costs, etc). Performance in terms of radiological protection and on-the-job safety, as well as environmental protection, is also monitored in order to give the broadest possible overview of nuclear power plant performance. The main technical results are presented on the basis of selected performance indicators. The results obtained by French units are benchmarked against those of other PWR facilities in operation around the world, in accordance with comparisons made by the World Association of Nuclear Operators (WANO). (author)

  3. Proton nuclear magnetic resonance and spectrophotometric studies of nickel(II)-iron(II) hybrid hemoglobins

    International Nuclear Information System (INIS)

    Shibayama, N.; Inubushi, T.; Morimoto, H.; Yonetani, T.

    1987-01-01

    Ni(II)-Fe(II) hybrid hemoglobins, α(Fe) 2 β(Ni) 2 and α(Ni) 2 β(Fe) 2 , have been characterized by proton nuclear magnetic resonance with Ni(II) protoporphyrin IX (Ni-PP) incorporated in apoprotein, which serves as a permanent deoxyheme. α(Fe) 2 β(Ni) 2 , α(Ni) 2 β(Fe) 2 , and NiHb commonly show exchangeable proton resonances at 11 and 14 ppm, due to hydrogen-bonded protons in a deoxy-like structure. Upon binding of carbon monoxide (CO) to α(Fe) 2 β(Ni) 2 , these resonances disappear at pH 6.5 to pH 8.5. On the other hand, the complementary hybrid α(Ni) 2 β(Fe-CO) 2 showed the 11 and 14 ppm resonances at low pH. Upon raising pH, the intensities of both resonances are reduced, although these changes are not synchronized. Electronic absorption spectra and hyperfine-shifted proton resonances indicate that the ligation of CO in the β(Fe) subunits induced changes in the coordination and spin states of Ni-PP in the α subunits. In a deoxy-like structure, the coordination of Ni-PP in the α subunits is predominantly in a low-spin (S = 0) four-coordination state, whereas in an oxy-like structure the contribution of a high-spin (S = 1) five-coordination state markedly increased. Ni-PP in the β subunits always takes a high-spin five-coordination state regardless of solution conditions and the state of ligation in the partner α(Fe) subunits. In the β(Ni) subunits, a significant downfield shift of the proximal histidyl N/sub δ/H resonance and a change in the absorption spectrum of Ni-PP were detected, upon changing the quaternary structure of the hybrid. The chemical shifts were analyzed in terms of the E11-Val methyls vs. the porphyrin rings in hybrid Hbs

  4. Application of nuclear magnetic resonance in osteoporosis evaluation; Aplicacoes de ressonancia magnetica nuclear na avaliacao de osteoporose

    Energy Technology Data Exchange (ETDEWEB)

    Giannoni, Ricardo A., E-mail: giannoni@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Montrazi, Elton T.; Bonagamba, Tito J., E-mail: elton.montrazi@gmail.com, E-mail: tito@ifsc.usp.br [Universidade de Sao Paulo (IFSC/USP), Sao Carlos, SP (Brazil). Inst. de Fisica; Cesar, Reinaldo, E-mail: reinaldofisica@gmail.com [Universidade de Sao Paulo (EESC/USP), Sao Carlos, SP (Brazil). Escola de Engenharia

    2013-07-01

    In this work, initially ceramic samples of known porosity were used. These ceramic samples were saturated with water. The nuclear magnetic resonance signal due to relaxation processes that the hydrogen nucleus water contained in the pores of this ceramic material was measured. Then these samples were subjected to a process of drying and measures successively. As the water contained in pores greater evaporates the intensity of signal decreases and shows the sign because of the smaller pores. The analysis of this drying process gives a qualitative assessment of the pore size of the material. In a second step, bones of animals of unknown porosity underwent the same methodology for evaluating osteoporosis. Also a sample of human vertebra in a unique manner, with the same purpose was measured. Combined with other techniques is a quantitative evaluation of the possible porosity.

  5. Measurement of specific heat and specific absorption rate by nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Gultekin, David H., E-mail: david.gultekin@aya.yale.edu [Department of Electrical Engineering, Yale University, New Haven, CT 06520 (United States); Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY 10065 (United States); Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065 (United States); Institute of Imaging Science, Vanderbilt University, Nashville, TN 37232 (United States); Gore, John C. [Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37232 (United States); Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN 37232 (United States); Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232 (United States); Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37232 (United States); Institute of Imaging Science, Vanderbilt University, Nashville, TN 37232 (United States)

    2010-05-20

    We evaluate a nuclear magnetic resonance (NMR) method of calorimetry for the measurement of specific heat (c{sub p}) and specific absorption rate (SAR) in liquids. The feasibility of NMR calorimetry is demonstrated by experimental measurements of water, ethylene glycol and glycerol using any of three different NMR parameters (chemical shift, spin-spin relaxation rate and equilibrium nuclear magnetization). The method involves heating the sample using a continuous wave laser beam and measuring the temporal variation of the spatially averaged NMR parameter by non-invasive means. The temporal variation of the spatially averaged NMR parameter as a function of thermal power yields the ratio of the heat capacity to the respective nuclear thermal coefficient, from which the specific heat can be determined for the substance. The specific absorption rate is obtained by subjecting the liquid to heating by two types of radiation, radiofrequency (RF) and near-infrared (NIR), and by measuring the change in the nuclear spin phase shift by a gradient echo imaging sequence. These studies suggest NMR may be a useful tool for measurements of the thermal properties of liquids.

  6. Carbon nuclear magnetic resonance spectroscopic fingerprinting of commercial gasoline: pattern-recognition analyses for screening quality control purposes.

    Science.gov (United States)

    Flumignan, Danilo Luiz; Boralle, Nivaldo; Oliveira, José Eduardo de

    2010-06-30

    In this work, the combination of carbon nuclear magnetic resonance ((13)C NMR) fingerprinting with pattern-recognition analyses provides an original and alternative approach to screening commercial gasoline quality. Soft Independent Modelling of Class Analogy (SIMCA) was performed on spectroscopic fingerprints to classify representative commercial gasoline samples, which were selected by Hierarchical Cluster Analyses (HCA) over several months in retails services of gas stations, into previously quality-defined classes. Following optimized (13)C NMR-SIMCA algorithm, sensitivity values were obtained in the training set (99.0%), with leave-one-out cross-validation, and external prediction set (92.0%). Governmental laboratories could employ this method as a rapid screening analysis to discourage adulteration practices. Copyright 2010 Elsevier B.V. All rights reserved.

  7. Identification and quantification of polycarboxylates in detergent products using off-line size exclusion chromatography-nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Visser, Ilona, E-mail: ilona.visser@unilever.com [Unilever Research and Development Vlaardingen, Olivier van Noortlaan 120, PO box 114, 3130 AC Vlaardingen (Netherlands); Klinkenberg, Monique; Hoos, Peter; Janssen, Hans-Gerd; Duynhoven, John van [Unilever Research and Development Vlaardingen, Olivier van Noortlaan 120, PO box 114, 3130 AC Vlaardingen (Netherlands)

    2009-11-03

    The performance of many contemporary detergent products critically depends on polymers. Water-soluble polycarboxylates represent an important class of detergent polymers, and their quantitative assessment in detergent matrices stands as a considerable challenge. The presence of high levels of surfactants is a major complication, due to the strong tendency of surfactants to form micelles and to interact with the polymers. First, we addressed critical steps in the subsequent combined use of liquid extraction and off-line size exclusion chromatography-nuclear magnetic resonance (SEC-NMR) for identification and quantification of polycarboxylates in detergent products. Next, the different steps in the off-line SEC-NMR procedure were optimized with respect to precision and accuracy. This resulted in recoveries of more than 80% for maleic acid/acrylic acid copolymers; in detergent products a proportional bias of 30% is achieved. The method showed good precision with a relative standard deviation of within-laboratory reproducibility between 5% and 14%.

  8. Identification and quantification of polycarboxylates in detergent products using off-line size exclusion chromatography-nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Visser, Ilona; Klinkenberg, Monique; Hoos, Peter; Janssen, Hans-Gerd; Duynhoven, John van

    2009-01-01

    The performance of many contemporary detergent products critically depends on polymers. Water-soluble polycarboxylates represent an important class of detergent polymers, and their quantitative assessment in detergent matrices stands as a considerable challenge. The presence of high levels of surfactants is a major complication, due to the strong tendency of surfactants to form micelles and to interact with the polymers. First, we addressed critical steps in the subsequent combined use of liquid extraction and off-line size exclusion chromatography-nuclear magnetic resonance (SEC-NMR) for identification and quantification of polycarboxylates in detergent products. Next, the different steps in the off-line SEC-NMR procedure were optimized with respect to precision and accuracy. This resulted in recoveries of more than 80% for maleic acid/acrylic acid copolymers; in detergent products a proportional bias of 30% is achieved. The method showed good precision with a relative standard deviation of within-laboratory reproducibility between 5% and 14%.

  9. Nuclear quadrupole resonance applied for arsenic oxide study; Estudo do oxido de arsenio atraves de ressonancia quadrupolar nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Correia, J A.S.

    1991-04-01

    The objectives of this study are mounting a pulsed Nuclear Quadrupole Resonance (NQR) building a flow cryostat capable of varying the temperature continuously from 77 K to 340 K and using the spectrometer and the cryostat to study the polycrystalline arsenic oxide. The spin-lattice relaxation time (T{sub 1}), the spin-spin relaxation time (T{sub 2}) and the resonance frequency are obtained as a function of temperature. These data are obtained in 77 to 330 K interval. The relaxation times are obtained using the spin echo technique. The spin echo phenomenon is due to refocusing spins, when a 180{sup 0} C pulse is applied after a 90{sup 0} C pulse. The spin-lattice relaxation time is obtained using the plot of echo amplitude versus the repetition time. The spin-spin relaxation time is obtained using the plot of echo amplitude versus the separation between the 90{sup 0} C - 180{sup 0} C pulses. The theory developed by Bayer is used to explain the spin-lattice relaxation time and the frequency temperature dependence. The spin-spin relaxation time is discussed using the Bloch equations. (author).

  10. Sunflower oil ozonation. Following of the reaction by proton Nuclear Magnetic Resonance

    International Nuclear Information System (INIS)

    Diaz Gomez, Maritza F.

    2005-01-01

    Previous studies have demonstrated that the technique of Proton Nuclear Magnetic Resonance can be used for the pursuit of the reaction between the ozone and the unsaturated fatty acids. It's carried out the sunflower oil ozonization to different applied dose of ozone and the index of peroxides and the concentration of aldehydes are determined. The main reaction products were identified by Proton Nuclear Magnetic Resonance Spectroscopy (NMR 1 H). The intensities of the signs were used to follow the advance of the reaction between the ozone and the sunflower oil. It is was carried out until obtaining an index of peroxides of 1 202 mmol-equiv/kg. The intensities of the signs of the olefinic protons diminish with a gradual increment in the dose of applied ozone, but without ending up disappearing completely. The ozonides of Criegee obtained to applied dose of ozone of 107,1 mg/g were approximately bigger 7,4 times that those obtained at the beginning from the reaction to applied dose of ozone of 15,3 mg/g. The aldehydes protons were observed as a sign of weak intensity in all the spectra. The signs belonging to the olenifics protons of the hydroperoxides in d = 5,55 ppm increases with the increment of the applied dose of ozone. You concludes that to higher applied dose of ozone, haggler is the advance of the ozonization reaction, what belongs together with a bigger formation of oxygenated compounds

  11. Nuclear magnetic resonance spectroscopy for determining the functional content of organic aerosols: A review

    International Nuclear Information System (INIS)

    Chalbot, Marie-Cecile G.; Kavouras, Ilias G.

    2014-01-01

    The knowledge deficit of organic aerosol (OA) composition has been identified as the most important factor limiting our understanding of the atmospheric fate and implications of aerosol. The efforts to chemically characterize OA include the increasing utilization of nuclear magnetic resonance spectroscopy (NMR). Since 1998, the functional composition of different types, sizes and fractions of OA has been studied with one-dimensional, two-dimensional and solid state proton and carbon-13 NMR. This led to the use of functional group ratios to reconcile the most important sources of OA, including secondary organic aerosol and initial source apportionment using positive matrix factorization. Future research efforts may be directed towards the optimization of experimental parameters, detailed NMR experiments and analysis by pattern recognition methods to identify the chemical components, determination of the NMR fingerprints of OA sources and solid state NMR to study the content of OA as a whole. - Highlights: • Organic aerosol composition by 1 H- and 13 C-NMR spectroscopy. • NMR fingerprints of specific sources, types and sizes of organic aerosol. • Source reconciliation and apportionment using NMR spectroscopy. • Research priorities towards understanding organic aerosol composition and origin. - This review presents the recent advances on the characterization of organic aerosol composition using nuclear magnetic resonance spectroscopy

  12. Determination of bound and unbound water in dental alginate irreversible hydrocolloid by nuclear magnetic resonance spectroscopy.

    Science.gov (United States)

    Fellows, C M; Thomas, G A

    2009-04-01

    Alginate materials are considered unsuitable for precise fixed prosthetic rehabilitation due to their tendency to undergo spontaneous syneresis. Commercial alginate impression materials were investigated using Nuclear Magnetic Resonance (NMR) Spectroscopy to probe the relation between changes in the microscopic water environment and dimensional change to obtain a better understanding of spontaneous syneresis. NMR was used to measure the spin-lattice relaxation times (T(1)) of (1)H nuclei in water in alginate matrices to characterize changes in gel structure over time. These results were related to the dimensional stabilities of the alginate impression materials, their chemical compositions, and the Moisture Sorption Isotherms (MSI) obtained by incubation at fixed relative humidities. The rate of change of T(1) with time was found to be a better predictor of dimensional stability than MSI. The greatest dimensional stability for the alginate powders investigated was associated with a high filler:alginate ratio and a high Ca:Na ratio. Nuclear magnetic resonance spectroscopy may used to measure changes in alginate impression materials under conditions where no dimensional change can be observed directly. Changes occurred rapidly even at 100% humidity, suggesting the dimensional stability of alginate impression materials is partially independent of the rate of dehydration. The results may open a way to formulate alginate impression materials more suitable for precise fabrication of dental prostheses.

  13. 151Eu nuclear resonant inelastic scattering of Eu3Pd20Ge6

    International Nuclear Information System (INIS)

    Tsutsui, S.; Yoda, Y.; Kobayashi, Y.; Higashitaniguchi, S.; Seto, M.; Kitagawa, J.; Takabatake, T.

    2010-01-01

    151 Eu nuclear resonant inelastic scattering of Eu 3 Pd 20 Ge 6 . The Eu partial phonon density of states (DOS) in Eu 3 Pd 20 Ge 6 are investigated using 151 Eu nuclear resonance inelastic scattering (NRIS). 151 Eu NRIS was carried out at BL09XU of SPring-8. Significant temperature dependence was found in the partial phonon DOS. Judging from the valence change at the Eu 4a site and the comparison with the ab initio calculation of Eu 3 Pd 20 Ge 6 , the change of the Eu DOS is caused by the electronic states. On the other hand, significant acoustic contribution was found even at the guest site of the Eu ones. In addition, slower average velocity than transverse sound velocity was obtained by Eu partial phonon DOS. Considering that heat is carried by the acoustic phonon in materials, the present results demonstrate that the moderate thermal insulation in Eu 3 Pd 20 Ge 6 is connected with the observation of slow average sound velocity at the Eu sites. (K.F.)

  14. Molecular Dynamics of Water in Wood Studied by Fast Field Cycling Nuclear Magnetic Resonance Relaxometry

    Directory of Open Access Journals (Sweden)

    Xinyu Li

    2016-01-01

    Full Text Available Water plays a very important role in wood and wood products. The molecular motion of water in wood is susceptible to thermal activation. Thermal energy makes water molecules more active and weakens the force between water and wood; therefore, the water molecules dynamic properties are greatly influenced. Molecular dynamics study is important for wood drying; this paper therefore focuses on water molecular dynamics in wood through fast field cycling nuclear magnetic resonance relaxometry techniques. The results show that the spin-lattice relaxation rate decreases with the Larmor frequency. Nuclear magnetic resonance dispersion profiles at different temperatures could separate the relaxation contribution of water in bigger pores and smaller pores. The T1 distribution from wide to narrow at 10 MHz Larmor frequency reflects the shrinkage of pore size with the higher temperature. The dependence of spin-lattice relaxation rate on correlation time for water molecular motion based on BPP (proposed by Bloembergen, Purcell, and Pound theory shows that water correlation time increases with higher temperature, and its activation energy, calculated using the Arrhenius transformation equation, is 9.06±0.53 kJ/mol.

  15. Characterization of polymer-type ionic conductors using nuclear magnetic resonance and thermal analysis. Humidity sensor

    International Nuclear Information System (INIS)

    Cavalcante, Maria Goretti.

    1992-04-01

    We report a study using Nuclear Magnetic Resonance (NMR), Thermogravimetry Analysis, Differential Scanning Calorimetry and Infrared Spectroscopy in polymeric complexes formed poly(ethylene oxide), (PEO), and lithium salts. These complexes have have shown a large potential for technological applications in batteries, sensors, etc. We developed and characterized humidity sensors and discussed how the humidity affects the conformation of the complexes, the mobility of ionic species, and the polymeric chains. The results indicate that the hydration affects the conformation of polymeric complexes by plasticizing the water, which induces a volumetric expansion in the PEO chain. The processes was completely reversible for the level of hydration studied. NMR was used to distinguish the movement of polymeric chains from the movement of the ionic species. From the analysis of the second moment of resonance lines from the study of the nuclear relaxation we were able to estimate the average distance between the ionic species and the proton in the complexes chains. The behaviour of spin -lattice relaxation of hydrogen and fluorine in the P(EO) - Li B F, as a function of temperature and frequency reflects the nature of the disorder and the complexity of the ionic conduction process in these materials. (author). 91 refs., 69 figs., 2 tabs

  16. Para-hydrogen raser delivers sub-millihertz resolution in nuclear magnetic resonance

    Science.gov (United States)

    Suefke, Martin; Lehmkuhl, Sören; Liebisch, Alexander; Blümich, Bernhard; Appelt, Stephan

    2017-06-01

    The precision of nuclear magnetic resonance spectroscopy (NMR) is limited by the signal-to-noise ratio, the measurement time Tm and the linewidth Δν = 1/(πT2). Overcoming the T 2 limit is possible if the nuclear spins of a molecule emit continuous radio waves. Lasers and masers are self-organized systems which emit coherent radiation in the optical and micro-wave regime. Both are based on creating a population inversion of specific energy states. Here we show continuous oscillations of proton spins of organic molecules in the radiofrequency regime (raser). We achieve this by coupling a population inversion created through signal amplification by reversible exchange (SABRE) to a high-quality-factor resonator. For the case of 15N labelled molecules, we observe multi-mode raser activity, which reports different spin quantum states. The corresponding 1H-15N J-coupled NMR spectra exhibit unprecedented sub-millihertz resolution and can be explained assuming two-spin ordered quantum states. Our findings demonstrate a substantial improvement in the frequency resolution of NMR.

  17. 8. Nuclear magnetic resonance users meeting; 1. Luso-Brazilian NMR meeting. Abstracts

    International Nuclear Information System (INIS)

    2001-01-01

    The NMR Users Meeting is held every year in Brazil and its eighth edition took place from May 7 - 11, 2001 together with the first Luso-Brazilian Meeting on Nuclear Magnetic Resonance. The extended abstracts book comprise: ten major conferences, four plenary lectures delivered by enterprise representatives (three from USA and one from Germany), six talks about the state-of-the-art of NMR methods (especially bi and tri-dimensional new techniques) and summaries of results from one hundred and twenty four research works. Among these research results which have been discussed, one hundred and sixteen were presented as congress panels/posters and eight as oral communications. The major topics of the scientific and technological research works are thus distributed: 63% in chemical sciences (mainly structural elucidation and stereochemistry of organic compounds and dynamical studies of chemical reactions), 19% in materials science (including petroleum), 8% in applied life sciences (agricultural and food sciences, biological sciences and medicine), 8% about theoretical aspects related to nuclear magnetic resonance and 2% regarding improvements in NMR instrumental techniques

  18. Solid-state nuclear magnetic resonance studies of phosphorus and boron in coals and combustion residues

    Energy Technology Data Exchange (ETDEWEB)

    Burchill, P.; Howarth, O.W.; Richards, D.G.; Sword, B.J. (British Coal Corporation, Stoke Orchard (UK). Coal Research Establishment)

    1990-04-01

    Solid-state nuclear magnetic resonance spectroscopy with magic angle spinning (MAS-n.m.r.) was used to study the occurrence of phosphorus and boron in coal, and their fate on combustion. These elements are only minor components of coal, but may significantly influence the utilization properties. {sup 31} P MAS-n.m.r. spectroscopy has confirmed that phosphorus is present in coal predominantly as apatite. This mineral is thermally stable under oxidizing conditions, and survives largely unaltered in high temperature ashes. However, under the semi-reducing bed conditions of certain stoker-fired boilers, it may be decomposed, volatilizing the phosphorus. The {sup 31}P MAS-n.m.r. spectra of bonded deposits show phosphorus in a markedly different coordination environment to that in apatite, the chemical shift suggesting aluminium phosphate or boron phosphate. {sup 11}B MAS-n.m.r. spectra of coals exhibit resonances due to both trigonal and tetrahedrally coordinated boron. Trigonal boron is probably present as tourmaline, but the nature of the tetrahedral boron is less certain; it may be held in tetrahedral sites within certain clay minerals. In common with phosphorus, boron may be volatilized during combustion. The {sup 11}B MAS-n.m.r. spectra of bonded deposits show a tetrahedral resonance with a chemical shift quite consistent with that of boron phosphate. 39 refs., 9 figs., 5 tabs.

  19. How to analyze a nuclear magnetic resonance image. Application to the pelvis

    International Nuclear Information System (INIS)

    Parienty, R.; Lavayssiere, R.

    1983-01-01

    Nuclear magnetic resonance (NMR) is based on the behaviour of some atomic nuclei when they are placed in a magnetic field and subjected to radiofrequency waves of a specific length. The resonance signals they emit under such conditions are collected as localized digital data which are used to construct an image. The signals vary according to multiple tissue characteristics, notably proton density, relaxation times T1 and T2 and, where applicable, blood flow direction and velocity. The relative influences exerted by these tissue factors on resonance signals can be evaluated by altering the technical parameters of the examination, that is practically the radiofrequency wave sequence. Special formulae make it possible to predict signal variations and to increase, decrease or even reverse contrast, thus obtaining as many morphological or functional images of the different media in the body. NMR semiology therefore is copious, complex and variable, but a diagrammatic description of the interplay between parameters provides a key to elementary analysis. Images of pelvic structures taken as examples illustrate the necessity to select the exploratory procedure according to the purpose of the exploration or to manipulate sequences with greater safety [fr

  20. Detection of nuclear magnetic resonance in the microtesla range using a high Tc dc-SQUID

    Science.gov (United States)

    Wang, Ning; Jin, Yirong; Li, Shao; Ren, Yufeng; Tian, Ye; Chen, Yingfei; Li, Jie; Chen, Genghua; Zheng, Dongning

    2012-12-01

    We have detected the ultra-low field nuclear magnetic resonance signal from water samples using a high-Tc dc-SQUID sensor. The measurements were carried out in a homemade magnetically shielded room. Resonance spectra of 1H from tap water and other substance samples were obtained in the field range from 7-110μT corresponding to resonance frequency 300-4.68kHz. Two kind of experimental systems were built, the first one is a directly coupled system, its signal to noise ratio in a single-shot measurement is around 4 for about 15 ml water. The second one used a Cu coil to transfer the flux to the SQUID sensor. Signal to noise ratio was improved to about 20 in a single-shot measurement for 5ml water, which benefits from the improvement of coupling efficiency. The effect of residual gradient in the magnetically shielded room was also investigated. J-coupling of 2,2,2-Trifluoroethyl alcohol was measured, the peaks are consistent with high field results.